1,545 research outputs found
Ethyl α-âphenylhydrazono-â2-âfuranpropionate
The title compd. is orthorhombic, space group Pca21, with a 11.115(1)â, b 8.170(1)â, and c 15.341(1) Ă
; Z = 4 for dm = 1.290 and dc = 1.293. The structure was solved by direct methods and refined to an R of 0.041 for 1033 reflections. At. coordinates are given. The structure conforms to the non-âH-âbonded α form. The hydrazine moiety is planar with sp2 hybridization at the N and neighboring atoms. Intermol. N-âH...O hydrogen bonds link the mols. into chains along a
Measurement of the elastic tensor of SmScO3 and NdSc03 using resonant ultrasound spectroscopy with ab initio calculations
The complete elastic tensors of SmScO3 and NdScO3 were measured using resonant ultrasound spectroscopy (RUS) in combination with ab-initio calculations. Measurement of the elastic tensor of these recently synthesized single crystal RE scandates is essential for understanding dynamic lattice applications including phonon confinement, strain induced thin film growth and superlattice construction. On average, the experimental elastic constants differed by less than 5% of the theoretical values, further validating the accuracy of modern ab-initio calculations as a means of estimating the initial elastic constants used in RUS measurements
HESFIRE: a global fire model to explore the role of anthropogenic and weather drivers
Vegetation fires are a major driver of ecosystem
dynamics and greenhouse gas emissions. Anticipating potential
changes in fire activity and their impacts relies first
on a realistic model of fire activity (e.g., fire incidence and
interannual variability) and second on a model accounting
for fire impacts (e.g., mortality and emissions). In this paper,
we focus on our understanding of fire activity and describe
a new fire model, HESFIRE (HumanâEarth System
FIRE), which integrates the influence of weather, vegetation
characteristics, and human activities on fires in a stand-alone
framework. It was developed with a particular emphasis on
allowing fires to spread over consecutive days given their major
contribution to burned areas in many ecosystems. A subset
of the model parameters was calibrated through an optimization
procedure using observation data to enhance our
knowledge of regional drivers of fire activity and improve
the performance of the model on a global scale. Modeled fire
activity showed reasonable agreement with observations of
burned area, fire seasonality, and interannual variability in
many regions, including for spatial and temporal domains not
included in the optimization procedure. Significant discrepancies
are investigated, most notably regarding fires in boreal
regions and in xeric ecosystems and also fire size distribution.
The sensitivity of fire activity to model parameters is
analyzed to explore the dominance of specific drivers across
regions and ecosystems. The characteristics of HESFIRE and
the outcome of its evaluation provide insights into the influence of anthropogenic activities and weather, and their interactions,
on fire activityinfo:eu-repo/semantics/publishedVersio
Global fire activity patterns (1996-2006) and climatic influence: an analysis using World Fire Atlas
Vegetation fires have been acknowledged as an environmental
process of global scale, which affects the chemical
composition of the troposphere, and has profound ecological
and climatic impacts. However, considerable uncertainty
remains, especially concerning intra and inter-annual
variability of fire incidence. The main goals of our globalscale
study were to characterise spatial-temporal patterns of
fire activity, to identify broad geographical areas with similar
vegetation fire dynamics, and to analyse the relationship
between fire activity and the El NiËno-Southern Oscillation.
This study relies on 10 years (mid 1996âmid
2006) of screened European Space Agency World Fire Atlas
(WFA) data, obtained from Along Track Scanning Radiometer
(ATSR) and Advanced ATSR (AATSR) imagery.
Empirical Orthogonal Function analysis was used to reduce
the dimensionality of the dataset. Regions of homogeneous
fire dynamics were identified with cluster analysis, and interpreted
based on their eco-climatic characteristics. The
impact of 1997â1998 El NiËno is clearly dominant over the
study period, causing increased fire activity in a variety of
regions and ecosystems, with variable timing. Overall, this
study provides the first global decadal assessment of spatialtemporal
fire variability and confirms the usefulness of the
screened WFA for global fire ecoclimatology researc
Configuration mixing in Pb : band structure and electromagnetic properties
In the present paper, we carry out a detailed analysis of the presence and
mixing of various families of collective bands in Pb. Making use of the
interacting boson model, we construct a particular intermediate basis that can
be associated with the unperturbed bands used in more phenomenological studies.
We use the E2 decay to construct a set of collective bands and discuss in
detail the B(E2)-values. We also perform an analysis of these theoretical
results (Q, B(E2)) to deduce an intrinsic quadrupole moment and the associated
quadrupole deformation parameter, using an axially deformed rotor model.Comment: submitted to pr
Passive scalar convection in 2D long-range delta-correlated velocity field: Exact results
The letter presents new field-theoretical approach to 2D passive scalar
problem. The Gaussian form of the distribution for the Lyapunov exponent is
derived and its parameters are found explicitly.Comment: 11 pages, RevTex 3.0, IFUM-94/455/January-F
Equilibrium states of the pressure function for products of matrices
Let be a non-trivial family of complex
matrices, in the sense that for any , there exists such that . Let be the pressure function of . We show
that for each , there are at most ergodic -equilibrium states of
, and each of them satisfies certain Gibbs property.Comment: 12 pages. To appear in DCD
Novel anisotropy in the superconducting gap structure of Bi_{2}Sr_{2}CaCu_{2}O_{8+\delta} probed by quasiparticle heat transport
Since the nature of pairing interactions is manifested in the superconducting
gap symmetry, the exact gap structure, particularly any deviation from the
simple d_{x^2-y^2} symmetry, would help elucidating the pairing mechanism in
high-T_c cuprates. Anisotropic heat transport measurement in
Bi_{2}Sr_{2}CaCu_{2}O_{8+\delta} (Bi-2212) reveals that the quasiparticle
populations are different for the two nodal directions and thus the gap
structure must be uniquely anisotropic, suggesting that pairing is governed by
interactions with a rather complicated anisotropy. Intriguingly, it is found
that the "plateau" in the magnetic-field dependence of the thermal conductivity
is observed only in the b-axis transport.Comment: 4 pages, 5 figures, accepted for publication in Phys. Rev. Let
Evolutionary Analysis of Mitogenomes from Parasitic and Free-Living Flatworms
Copyright: © 2015 SolĂ et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. The attached file is the published version of the article
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