1,044 research outputs found
Bulletin No. 32: The Connecticut College Arboretum - Its Sixth Decade and a Detailed History of the Land
Multi‐Element Surface Coating of Layered Ni‐Rich Oxide Cathode Materials and Their Long‐Term Cycling Performance in Lithium‐Ion Batteries
The energy density of layered oxide cathode materials increases with their Ni content, while the stability decreases and degradation becomes more severe. A common strategy to mitigate or prevent degradation is the application of protective coatings on the particle surfaces. In this article, a room-tem-perature, liquid-phase reaction of trimethylaluminum (TMA) and tetraethyl orthosilicate (TEOS) with adsorbed moisture on either LiNi0.85Co0.10Mn0.05O2or LiNiO2, yielding a hybrid coating that shows synergetic benefits compared to coatings from TMA and TEOS individually, is reported. The surface layer is investigated in long-term pouch full-cell studies as well as by electron micros-copy, X-ray photoelectron spectroscopy, and differential electrochemical mass spectrometry, demonstrating that it prevents degradation primarily by a fluorine-scavenging effect, and by reducing the extent of rock salt-type phase formation
The SN 393 -- SNR RX J1713.7-3946 (G347.3-0.5) Connection
Although the connection of the Chinese "guest" star of 393 AD with the
Galactic supernova remnant RX J1713.7-3946 (G347.3-0.5) made by Wang et al. in
1997 is consistent with the remnant's relatively young properties and the guest
star's projected position within the `tail' of the constellation Scorpius,
there are difficulties with such an association. The brief Chinese texts
concerning the 393 AD guest star make no comment about its apparent brightness
stating only that it disappeared after 8 months. However, at the remnant's
current estimated 1 - 1.3 kpc distance and A_v ~ 3 mag, its supernova should
have been a visually bright object at maximum light (-3.5 to -5.0 mag) and
would have remained visible for over a year. The peak brightness ~ 0 magnitude
adopted by Wang et al. and others would require the RX J1713.7-3946 supernova
to have been a very subluminous supernova event similar to or fainter than
CCSNe like SN 2005cs. We also note problems connecting SN 393 with a European
record in which the Roman poet Claudian describes a visually brilliant star in
the heavens around 393 AD that could be readily seen even in midday. Although
several authors have suggested this account may be a reference to the Chinese
supernova of 393, Scorpius would not be visible near midday in March when the
Chinese first reported the 393 guest star. We review both the Chinese and Roman
accounts and calculate probable visual brightnesses for a range of supernova
subtypes and conclude that neither the Chinese nor the Roman descriptions are
easily reconciled with an expected RX J1713.7-3946 supernova brightness and
duration.Comment: 7 pages includes 2 tables. Accepted for publication in AJ. Revised
text regarding subluminous SN
Responding to the UN sustainability goals in transdisciplinary partnership through network action learning
The global water crisis, an enormous concern according to the World Economic Forum, poses a significant challenge to long-term sustainability, exacerbated by the high energy demand associated with water supply and treatment. As the renewable energy sector grows, the need for green technologies to support the water-energy nexus becomes evident. However, mere technological advancements are insufficient to address complex water-related challenges. This paper presents a transdisciplinary collaborative effort involving engineers, geographers, management researchers, and environmentalists working with practitioners in a cross-border network. The study explores through action learning research how, in a transdisciplinary partnership, network action learning influences the exploration and implementation of novel green technology and the development of innovation capabilities. The research is structured around three themes: green technology platforms, policy support and guidance, and dissemination and collaboration. It identifies the factors impacting technology exploration and application and how concurrently green innovation capabilities are developed. The study emphasizes the significance of transdisciplinary collaboration and offers valuable insights into addressing UN Sustainability Goals related to clean water, sustainable industry, and partnerships. It contributes to innovation capability theory and provides practical guidance to researchers, practitioners, and policymakers, emphasizing the need for holistic approaches to address the water-energy crisis and achieve sustainable development
AMI observations of unmatched Planck ERCSC LFI sources at 15.75 GHz
The Planck Early Release Compact Source Catalogue includes 26 sources with no
obvious matches in other radio catalogues (of primarily extragalactic sources).
Here we present observations made with the Arcminute Microkelvin Imager Small
Array (AMI SA) at 15.75 GHz of the eight of the unmatched sources at
declination > +10 degrees. Of the eight, four are detected and are associated
with known objects. The other four are not detected with the AMI SA, and are
thought to be spurious.Comment: 6 pages, 5 figures, 4 table
Two or more dexamethasone intravitreal implants as monotherapy or in combination therapy for macular edema in retinal vein occlusion: subgroup analysis of a retrospective chart review study
Recognizing true H5N1 infections in humans during confirmed outbreaks.
INTRODUCTION: The goal of this study was to evaluate whether any characteristics that are evident at presentation for urgent medical attention could be used to differentiate cases of H5N1 in the absence of viral testing. METHODOLOGY: Information about exposure to poultry, clinical signs and symptoms, treatments, and outcomes was abstracted from existing data in the global avian influenza registry (www.avianfluregistry.org) using standardized data collection tools for documented and possible cases of H5N1 infection who presented for medical attention between 2005-2011 during known H5N1 outbreaks in Azerbaijan, Indonesia, Pakistan and Turkey. RESULTS: Demography, exposure to poultry, and presenting symptoms were compared, with only the common symptoms of fever and headache presenting significantly more frequently in confirmed H5N1 cases than in possible cases. Reported exposure to infected humans was also more common in confirmed cases. In contrast, unexplained respiratory illness, sore throat, excess sputum production, and rhinorrhea were more frequent in possible cases. Overall, oseltamivir treatment showed a survival benefit, with the greatest benefit shown in H5N1 cases who were treated within two days of symptom onset (51% reduction in case fatality). CONCLUSION: Since prompt treatment with antivirals conferred a strong survival benefit for H5N1 cases, presumptive antiviral treatment should be considered for all possible cases presenting during an outbreak of H5N1 as a potentially life-saving measure
Black Hole Spectroscopy: Testing General Relativity through Gravitational Wave Observations
Assuming that general relativity is the correct theory of gravity in the
strong field limit, can gravitational wave observations distinguish between
black hole and other compact object sources? Alternatively, can gravitational
wave observations provide a test of one of the fundamental predictions of
general relativity? Here we describe a definitive test of the hypothesis that
observations of damped, sinusoidal gravitational waves originated from a black
hole or, alternatively, that nature respects the general relativistic no-hair
theorem. For astrophysical black holes, which have a negligible charge-to-mass
ratio, the black hole quasi-normal mode spectrum is characterized entirely by
the black hole mass and angular momentum and is unique to black holes. In a
different theory of gravity, or if the observed radiation arises from a
different source (e.g., a neutron star, strange matter or boson star), the
spectrum will be inconsistent with that predicted for general relativistic
black holes. We give a statistical characterization of the consistency between
the noisy observation and the theoretical predictions of general relativity,
together with a numerical example.Comment: 19 pages, 7 figure
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