530 research outputs found
Circular economy strategies for electric vehicle batteries reduce raw material reliance
The wide adoption of lithium-ion batteries used in electric vehicles will require increased natural resources for the automotive industry. The expected rapid increase in batteries could result in new resource challenges and supply-chain risks. To strengthen the resilience and sustainability of automotive supply chains and reduce primary resource requirements, circular economy strategies are needed. Here we illustrate how these strategies can reduce the extraction of primary raw materials, that is, cobalt supplies. Material flow analysis is applied to understand current and future flows of cobalt embedded in electric vehicle batteries across the European Union. A reference scenario is presented and compared with four strategies: technology-driven substitution and technology-driven reduction of cobalt, new business models to stimulate battery reuse/recycling and policy-driven strategy to increase recycling. We find that new technologies provide the most promising strategies to reduce the reliance on cobalt substantially but could result in burden shifting such as an increase in nickel demand. To avoid the latter, technological developments should be combined with an efficient recycling system. We conclude that more-ambitious circular economy strategies, at both government and business levels, are urgently needed to address current and future resource challenges across the supply chain successfully
A Search for Cold Dust around Neutron Stars
We present observations of nine radio pulsars using the
Heinrich-Hertz-Telescope at \lambda 0.87mm and the IRAM 30-m telescope at
\lambda 1.2mm in search for a cold dust around these sources. Five of the
program pulsars have been observed for the first time at the mm-wavelengths.
The results are consistent with the absence of circumpulsar disks that would be
massive enough () to support planet formation according to
the scenarios envisioned for solar-type stars, but they do not exclude lower
mass () disks for a wide range of grain sizes. These
conclusions confirm the previously published results and, together with the
current lack of further detections of pulsar planets, they suggest that planet
formation around neutron stars is not a common phenomenon.Comment: 5 pages, 1 figure, accepted for publication in A&
The VLA Low-frequency Sky Survey
The Very Large Array (VLA) Low-frequency Sky Survey (VLSS) has imaged 95% of
the 3*pi sr of sky north of declination = -30 degrees at a frequency of 74 MHz
(4 meter wavelength). The resolution is 80" (FWHM) throughout, and the typical
RMS noise level is ~0.1 Jy/beam. The typical point-source detection limit is
0.7 Jy/beam and so far nearly 70,000 sources have been catalogued. This survey
used the 74 MHz system added to the VLA in 1998. It required new imaging
algorithms to remove the large ionospheric distortions at this very low
frequency throughout the entire ~11.9 degree field of view. This paper
describes the observation and data reduction methods used for the VLSS and
presents the survey images and source catalog. All of the calibrated images and
the source catalog are available online (http://lwa.nrl.navy.mil/VLSS) for use
by the astronomical community.Comment: 53 pages, including 3 tables and 15 figures. Has been accepted for
publication in the Astronomical Journa
Radio Spectra of Giant Radio Galaxies from RATAN-600 Data
Measurements of the flux densities of the extended components of seven giant
radio galaxies obtained using the RATAN-600 radio telescope at wavelengths of
6.25 and 13 cm ar e presented. The spectra of components of these radio
galaxies are constructed using these new RA TAN-600 data together with data
from the WENSS, NVSS, and GB6 surveys. The spectral indices in the stu died
frequency range are calculated, and the need for detailed estimates of the
integrated contributi on of such objects to the background emission is
demonstrated.Comment: 7 pages, 2 figures, 5 table
Rotation Measure Synthesis of Galactic Polarized Emission with the DRAO 26-m Telescope
Radio polarimetry at decimetre wavelengths is the principal source of
information on the Galactic magnetic field. The diffuse polarized emission is
strongly influenced by Faraday rotation in the magneto-ionic medium and
rotation measure is the prime quantity of interest, implying that all Stokes
parameters must be measured over wide frequency bands with many frequency
channels. The DRAO 26-m Telescope has been equipped with a wideband feed, a
polarization transducer to deliver both hands of circular polarization, and a
receiver, all operating from 1277 to 1762 MHz. Half-power beamwidth is between
40 and 30 arcminutes. A digital FPGA spectrometer, based on commercially
available components, produces all Stokes parameters in 2048 frequency channels
over a 485-MHz bandwidth. Signals are digitized to 8 bits and a Fast Fourier
Transform is applied to each data stream. Stokes parameters are then generated
in each frequency channel. This instrument is in use at DRAO for a Northern sky
polarization survey. Observations consist of scans up and down the Meridian at
a drive rate of 0.9 degree per minute to give complete coverage of the sky
between declinations -30 degree and 90 degree. This paper presents a complete
description of the receiver and data acquisition system. Only a small fraction
of the frequency band of operation is allocated for radio astronomy, and about
20 percent of the data are lost to interference. The first 8 percent of data
from the survey are used for a proof-of-concept study, which has led to the
first application of Rotation Measure Synthesis to the diffuse Galactic
emission obtained with a single-antenna telescope. We find rotation measure
values for the diffuse emission as high as approximately 100 rad per square
metre, much higher than recorded in earlier work.Comment: Accepted for publication in The Astronomical Journa
Acceptance of Anxiety through Art Therapy: A Case Report Exploring How Anthroposophic Art Therapy Addresses Emotion Regulation and Executive Functioning
Anxiety is a major problem for many individuals, causing impairment in daily life. Art therapy is often deployed and although positive results are communicated in clinical practice, its effectiveness and working mechanisms have hardly been studied. Therefore, it is important to systematically describe the intervention process and to detect the working mechanisms to be able to evaluate them. Narrative case studies help to understand the intervention in more depth. A typical case file was selected for case reporting according to scientific (CARE & CARE-AAT) guidelines, with the aim to explore the therapeutic elements that contributed to the reduction of anxiety. The report describes the intervention process of a 54-year-old female, suffering from anxiety since childhood and diagnosed with panic disorder, agoraphobia, claustrophobia and hypochondria. After 14 sessions of anthroposophic art therapy, reduction of anxiety was shown, as well as improvements of emotion regulation and executive functioning. The client indicated that she became more tolerant and accepting towards her anxiety. She noted a softened attitude towards herself and her complaints, even one year after art therapy. The course of treatment suggests that aspects of emotion regulation and executive functioning were addressed through implicit learning processes in different art therapy assignments.Development Psychopathology in context: clinical setting
The Identification of Infrared Synchrotron Radiation from Cassiopeia A
We report the discovery of polarized flux at 2.2 micron from the bright shell
of the approximately 320 year old supernova remnant Cas A. The fractional
polarizations are comparable at 6 cm and 2.2 micron, and the polarization
angles are similar, demonstrating that synchrotron radiation from the same
relativistic plasma is being observed at these widely separated wavebands. The
relativistic electrons radiating at 2.2 micron have an energy of ~ 150 GeV,
(gamma ~ 3e5), assuming an ~500 microGauss magnetic field. The total intensity
at 2.2 micron lies close to the power law extrapolation from radio frequencies,
showing that relativistic particle acceleration is likely an ongoing process;
the infrared emitting electrons were accelerated no longer than ~80 years ago.
There is a small but significant concave curvature to the spectrum, as expected
if the accelerating shocks have been modified by the back pressure of the
cosmic rays; given calibration uncertainties, this conclusion must be
considered tentative at present. The 2.2 micron polarization angles and the
emission-line filaments observed by HST are both offset from the local radial
direction by 10 - 20 degrees, providing evidence that the magnetic fields in
Cas A are generated by Rayleigh-Taylor instabilities in the decelerating
ejecta.Comment: 11 pages, 3 figures, accepted for publication Ap
Discovery of Radio Outbursts in the Active Nucleus of M81
The low-luminosity active galactic nucleus of M81 has been monitored at
centimeter wavelengths since early 1993 as a by-product of radio programs to
study the radio emission from Supernova 1993J. The extensive data sets reveal
that the nucleus experienced several radio outbursts during the monitoring
period. At 2 and 3.6 cm, the main outburst occurred roughly in the beginning of
1993 September and lasted for approximately three months; at longer
wavelengths, the maximum flux density decreases, and the onset of the burst is
delayed. These characteristics qualitatively resemble the standard model for
adiabatically expanding radio sources, although certain discrepancies between
the observations and the theoretical predictions suggest that the model is too
simplistic. In addition to the large-amplitude, prolonged variations, we also
detected milder changes in the flux density at 3.6 cm and possibly at 6 cm on
short (less than 1 day) timescales. We discuss a possible association between
the radio activity and an optical flare observed during the period that the
nucleus was monitored at radio wavelengths.Comment: To appear in The Astronomical Journal. Latex, 18 pages including
embedded figures and table
Quantum effects in linguistic endeavors
Classifying the information content of neural spike trains in a linguistic
endeavor, an uncertainty relation emerges between the bit size of a word and
its duration. This uncertainty is associated with the task of synchronizing the
spike trains of different duration representing different words. The
uncertainty involves peculiar quantum features, so that word comparison amounts
to measurement-based-quantum computation. Such a quantum behavior explains the
onset and decay of the memory window connecting successive pieces of a
linguistic text. The behavior here discussed is applicable to other reported
evidences of quantum effects in human linguistic processes, so far lacking a
plausible framework, since either no efforts to assign an appropriate quantum
constant had been associated or speculating on microscopic processes dependent
on Planck's constant resulted in unrealistic decoherence times
Two years of INTEGRAL monitoring of GRS 1915+105 Part 1: multiwavelength coverage with INTEGRAL, RXTE, and the Ryle radio Telescope
(Abridged) We report the results of monitoring observations of the Galactic
microquasar GRS 1915+105 performed simultaneously with INTEGRAL and RXTE Ryle .
We present the results of the whole \integral campaign, report the sources that
are detected and their fluxes and identify the classes of variability in which
GRS 1915+105 is found. The accretion ejection connections are studied in a
model independent manner through the source light curves, hardness ratio, and
color color diagrams. During a period of steady ``hard'' X-ray state (the
so-called class chi) we observe a steady radio flux. We then turn to 3
particular observations during which we observe several types of soft X-ray
dips and spikes cycles, followed by radio flares. During these observations GRS
1915+105 is in the so-called nu, lambda, and beta classes of variability. The
observation of ejections during class lambda are the first ever reported. We
generalize the fact that a (non-major) discrete ejection always occurs, in GRS
1915+105, as a response to an X-ray sequence composed of a spectrally hard
X-ray dip terminated by an X-ray spike marking the disappearance of the hard
X-ray emission above 18 keV. We also identify the trigger of the ejection as
this X-ray spike. A possible correlation between the amplitude of the radio
flare and the duration of the X-ray dip is found in our data. In this case the
X-ray dips prior to ejections could be seen as the time during which the source
accumulates energy and material that is ejected later.Comment: 17 pages, 14 figures. Accepted for publication in ApJ, scheduled for
the March 20, 2008, vol676 issue. Table 3 has been degrade
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