511 research outputs found

    One- and two-proton transfer reactions with vibrational Nuclei

    Get PDF
    We extend a semiclassical model of transfer reactions to the case in which one of the collision partners is a vibrational nucleus. The model is applied to one- and two-proton stripping reactions in the 37Cl + 98Mo system, for which a rapid transition from normal to anomalous slope in the two proton transfer reaction at energies around the Coulomb barrier is experimentally observed. This behavior is satisfactorily reproduced by the present extension of the model.Comment: LaTeX, 10 pages, 1 figure (PostScript

    Gas around the bladder

    Get PDF

    Using SPOT Data and FRAGSTAS to Analyze the Relationship between Plant Diversity and Green Space Landscape Patterns in the Tropical Coastal City of Zhanjiang, China

    Get PDF
    Urban green spaces provide a host of ecosystem services, the quantity and structure of which play an important role in human well-being. Rapid urbanization may modify urban green spaces, having various effects on plant diversity. Tropical coastal cities have urbanized rapidly in recent decades, but few studies have been conducted with a focus on their green spaces. We studied the responses of cultivated and spontaneous plants, both key components of urban flora, to the landscape structure of urban green spaces and possible social drivers. We analyzed existing relationships between plant diversity indices, urban green space landscape metrics (using Systeme Probatoire d’Observation de la Terre (SPOT) data,), and social factors, including the type, population density, construction age, and GPS coordinates of each Urban Functional Unit, or UFU. We found that UFUs with more green space patches had higher cultivated and spontaneous species richness than those with fewer green space patches. Spontaneous species richness decreased when green space patches became fragmented, and it increased when green space patches were more connected (e.g., via land bridges). Conversely, cultivated species richness increased with green space patch fragmentation. The phylogenetic diversity of both cultivated and spontaneous plants were weakly associated with green space structure, which was strongly driven by land use. Old UFUs and those with larger populations had more green space patches overall, although they tended to be small and fragmented. Green space patch density was found to increase as the UFU age increased. From the viewpoint of knowledge transfer, understanding the effects and drivers of landscape patterns of urban green spaces could inform the development of improved policies and management of urban green space areas.Peer Reviewe

    Understorey plant community and light availability in conifer plantations and natural hardwood forests in Taiwan

    Get PDF
    Questions: What are the effects of replacing mixed species natural forests with Cryptomeria japonica plantations on understorey plant functional and species diversity? What is the role of the understorey light environment in determining understorey diversity and community in the two types of forest? Location: Subtropical northeast Taiwan. Methods: We examined light environments using hemispherical photography, and diversity and composition of understorey plants of a 35‐yr C. japonica plantation and an adjacent natural hardwood forest. Results: Understorey plant species richness was similar in the two forests, but the communities were different; only 18 of the 91 recorded understorey plant species occurred in both forests. Relative abundance of plants among different functional groups differed between the two forests. Relative numbers of shade‐tolerant and shade‐intolerant seedling individuals were also different between the two forest types with only one shade‐intolerant seedling in the plantation compared to 23 seedlings belonging to two species in the natural forest. In the natural forest 11 species of tree seedling were found, while in the plantation only five were found, and the seedling density was only one third of that in the natural forest. Across plots in both forests, understorey plant richness and diversity were negatively correlated with direct sunlight but not indirect sunlight, possibly because direct light plays a more important role in understorey plant growth. Conclusions: We report lower species and functional diversity and higher light availability in a natural hardwood forest than an adjacent 30‐yr C. japonica plantation, possibly due to the increased dominance of shade‐intolerant species associated with higher light availability. To maintain plant diversity, management efforts must be made to prevent localized losses of shade‐adapted understorey plants

    Distribution and density of the partition function zeros for the diamond-decorated Ising model

    Full text link
    Exact renormalization map of temperature between two successive decorated lattices is given, and the distribution of the partition function zeros in the complex temperature plane is obtained for any decoration-level. The rule governing the variation of the distribution pattern as the decoration-level changes is given. The densities of the zeros for the first two decoration-levels are calculated explicitly, and the qualitative features about the densities of higher decoration-levels are given by conjecture. The Julia set associated with the renormalization map is contained in the distribution of the zeros in the limit of infinite decoration level, and the formation of the Julia set in the course of increasing the decoration-level is given in terms of the variations of the zero density.Comment: 8 pages,8figure

    Rock Compaction Fault Displacement Evidence from Analysis of Sub-Parallel Subsurface Strata

    Get PDF
    Sedimentary units often show compaction variation across fault blocks resulting from jarring vertical shortening; a common occurrence in growth fault system innate to the Niger Delta. Rock displacement traceable on slip surface with varied dip was mapped on 3D seismic data. Interpretation done on available well logs reveal existing zones of sand formation that fairly correlates with compaction patterns seen on seismic lines across fault blocks with reference to vertical deviations in horizons across fault planes. These anomalies were stochastically analyzed for its topology effects using Density logs from the field in an attempt to ascertain the influence of rock strata on fault displacement and how this translates to compaction patterns. It was discovered that the effect of differential compaction propelled by wobbly underlying rocks primarily drives the local complexities imaged on the seismic data as varied turgid deformation zones also prolific from computed seismic attributes

    Rock Compaction Fault Displacement Evidence from Analysis of Sub-Parallel Subsurface Strata

    Get PDF
    Sedimentary units often show compaction variation across fault blocks resulting from jarring vertical shortening; a common occurrence in growth fault system innate to the Niger Delta. Rock displacement traceable on slip surface with varied dip was mapped on 3D seismic data. Interpretation done on available well logs reveal existing zones of sand formation that fairly correlates with compaction patterns seen on seismic lines across fault blocks with reference to vertical deviations in horizons across fault planes. These anomalies were stochastically analyzed for its topology effects using Density logs from the field in an attempt to ascertain the influence of rock strata on fault displacement and how this translates to compaction patterns. It was discovered that the effect of differential compaction propelled by wobbly underlying rocks primarily drives the local complexities imaged on the seismic data as varied turgid deformation zones also prolific from computed seismic attributes
    corecore