6,460 research outputs found
Growth and Longevity of Some Calcareous Fouling Organisms, Monterey Bay, California
A knowledge of the lifespan of an organism
is of value in understanding its life history.
Ecological succession, including rates and characteristics
of marine fouling, may be related to
organism longevity. Organic production can be
evaluated from growth and longevity data (e.g.,
Thorson, 1957). Our longevity analysis was
undertaken as part of an evaluation of rates of
biogenic sediment production by calcareous
organisms
Fluoropolymers and methods of applying fluoropolymers in molding processes
Fluoropolymers consisting of alternating perfluorocyclobutane and aryl ether linkages possess suitable properties for optical waveguides and other devices using refractive properties of the polymers. Perfluorocyclobutane (PFCB) polymers having aryl groups alternating on an ether chain have shown useful physical properties for optical waveguide applications. Processes for micromolding such polymeric films by replicating a pattern or image directly from a silicon master, rather than from a polydimethyl siloxane (PDMS) mold, are disclosed
Diffraction devices and methods
Fluoropolymers consisting of alternating perfluorocyclobutane and aryl ether linkages possess suitable properties for optical waveguides and other devices using refractive properties of the polymers. Perfluorocyclobutane (PFCB) polymers having aryl groups alternating on an ether chain have shown useful physical properties for optical waveguide applications. Processes for micromolding such polymeric films by replicating a pattern or image directly from a silicon master, rather than from a polydimethyl siloxane (PDMS) mold) are disclosed
Random copolymer compositions
Fluoropolymers consisting of alternating perfluorocyclobutane and aryl ether linkages possess suitable properties for optical waveguides and other devices using refractive properties of the polymers. Perfluorocyclobutane (PFCB) polymers having aryl groups alternating on an ether chain have shown useful physical properties for optical waveguide applications. Processes for micromolding such polymeric films by replicating a pattern or image directly from a silicon master, rather than from a polydimethyl siloxane (PDMS) mold, are disclosed
Mapping erosion risk at the basin scale in a Mediterranean environment with opencast coal mines to target restoration actions
34 páginas, 9 figurasRiver basin restoration and management is crucial for assuring the continued delivery of ecosystem services and for limiting potential hazards. Human activity, whether directly or indirectly, can induce erosion processes and drastically change the landscape and alter vital ecological functions. Mapping erosion risk before future restoration-management projects will help to reveal the priority areas and develop a hierarchy ordered according to need. For this purpose, we used the Revised Universal Soil Loss Equation (RUSLE) erosion model. We also applied a novel technique called GPVI (Genetic Programming Vegetation Index) in the Martín River basin in NE Spain (2,112 km2), which has a large coalfield located in the southern part of the basin. Approximately two-thirds (69%) of the area of the Martín basin presents low and medium soil loss rates, and one-third (31%) of the area presents high (18%), very high (10%), and irreversible (3%) erosion rates. The southern part of the basin is the most degraded and is strongly influenced by the topography. This work allows us to locate areas prone to erosional degradation processes to help create a buffer around the river and locate “spots” in need of restoration. We also checked the error estimation of the methodology because our soil maps do not include rock and bare rock areas. The usefulness of applying RUSLE for predicting degraded areas and the consequent directing of soil conservation–restoration actions at the basin scale is demonstrated. We highly recommend a field survey of the selected areas to prove the goodness of the model estimations.This work is part of the research and assistance agreement between Endesa S.A. and CSICPyrenean Institute of Ecology (IPE-CSIC). Funding for this study was provided by Endesa S.A.
A special acknowledge is given to Endesa Centro Minero Andorra (Teruel). Thanks are given
to, J. M. Garcia Ruiz, S. Begueria, E. Nadal, E. Moran-Tejera, and J.J. Jimenez for reviewing
and general advises during the development of this work, M. P. Errea, J. Zabalza, L. C. Alatorre
for assistance with GIS analysis, M. Angulo for R factor map, M. Pazos with statistical analysis,
and F. Reverberi for laboratory work. M. Trabucchi was in receipt of grant from JAE-CSIC
(Ref. I3P-BPD-2006).Peer reviewe
Unseeded One-Third Harmonic Generation in Optical Fibers
We propose a new concept to generate efficient one-third harmonic light from
an unseeded third harmonic process in optical fibers. Our concept is based on
the dynamic constant (Hamiltonian) of the nonlinear third harmonic generation
in optical fibers and includes a periodic array of nonlinear fibers and phase
compensation elements. We test our concept with a simulation of the nonlinear
interaction between the fundamental and third harmonic modes of a realistic
optical fiber, demonstrating high-efficiency one-third harmonic generation. Our
work opens a new approach to achieving the so far elusive one-third harmonic
generation in optical fibers
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