1,524 research outputs found
The chemical/physical and microbiological characteristics of typical bath and laundry waste waters
Chemical/physical and microbiological characteristics are studied of typical bath and laundry waters collected during a 12 day test in which the untreated waste waters were reused for toilet flush. Most significant changes were found for ammonia, color, methylene blue active substances, phosphates, sodium, sulfates, total organic carbon, total solids, and turbidity in comparison with tap water baseline. The mean total number of microorganisms detected in the waste waters ranged from 1 million to 10 to the 7th power cells/m1 and the mean number of possible coliforms ranged from 10 to the 5th power to 1 million. An accumulation of particulates and an objectible odor were detected in the tankage used during the 12 day reuse of the untreated waste waters. The combined bath and laundry waste waters from a family of four provided 91 percent of the toilet flush water for the same family
Classical Disordered Ground States: Super-Ideal Gases, and Stealth and Equi-Luminous Materials
Using a collective coordinate numerical optimization procedure, we construct
ground-state configurations of interacting particle systems in various space
dimensions so that the scattering of radiation exactly matches a prescribed
pattern for a set of wave vectors. We show that the constructed ground states
are, counterintuitively, disordered (i.e., possess no long-range order) in the
infinite-volume limit. We focus on three classes of configurations with unique
radiation scattering characteristics: (i)``stealth'' materials, which are
transparent to incident radiation at certain wavelengths; (ii)``super-ideal''
gases, which scatter radiation identically to that of an ensemble of ideal gas
configurations for a selected set of wave vectors; and (iii)``equi-luminous''
materials, which scatter radiation equally intensely for a selected set of wave
vectors. We find that ground-state configurations have an increased tendency to
contain clusters of particles as one increases the prescribed luminosity.
Limitations and consequences of this procedure are detailed.Comment: 44 pages, 16 figures, revtek
The tidal effects on the lithium abundance of binary systems with giant component
We analise the behavior of lithium abundance as a function of effective
temperature, projected rotational velocity, orbital period and eccentricity for
a sample of 68 binary systems with giant component and orbital period ranging
from about 10 to 6400 days. For these binary systems the Li abundances show a
gradual decrease with temperature, paralleling the well established result for
single giants. We have also observed a dependence of lithium content on
rotation. Binary systems with moderate to high rotation present also moderate
to high Li content. This study shows also that synchronized binary systems with
giant component seems to retain more of their original lithium than the
unsynchronized systems. For orbital periods lower than 100 to 250 days,
typically the period of synchronization for this kind of binary systems,
lithium depleted stars seems to be unusual. The suggestion is made that there
is an 'inhibited zone' in which synchronized binary systems with giant
component having lithium abundance lower than a threshold level should be
unusual.Comment: 6 pages, 3 Postscript figures, uses: aa.cls, psfig.st
The HgMn Binary Star Phi Herculis: Detection and Properties of the Secondary and Revision of the Elemental Abundances of the Primary
Observations of the Mercury-Manganese star Phi Herculis with the Navy
Prototype Optical Interferometer (NPOI) conclusively reveal the previously
unseen companion in this single-lined binary system. The NPOI data were used to
predict a spectral type of A8V for the secondary star Phi Her B. This
prediction was subsequently confirmed by spectroscopic observations obtained at
the Dominion Astrophysical Observatory. Phi Her B is rotating at 50 +/-3
km/sec, in contrast to the 8 km/sec lines of Phi Her A. Recognizing the lines
from the secondary permits one to separate them from those of the primary. The
abundance analysis of Phi Her A shows an abundance pattern similar to those of
other HgMn stars with Al being very underabundant and Sc, Cr, Mn, Zn, Ga, Sr,
Y, Zr, Ba, Ce, and Hg being very overabundant.Comment: Accepted to ApJ, 45 pages, 11 figure
Children and young people’s perspectives from UK lockdown: leisure-less experiences
If researchers are to understand the impacts of lockdown on children and young people, then the experiences of lockdown need to be explored from the perspective of the child. Young people participate in leisure for a multitude of reasons, yet, within the UK, children were largely unable to access their regular leisure activities for a six-month period during the first national lockdown. Within the context of this paper, leisure includes outdoor sports and physical activities within blue spaces. Following interviews with parents and young people (aged 11–16) focused on experiences of leisure during the Covid-19 pandemic, this qualitative study identified that children felt an intense sense of missing out on opportunities and found day-to-day life without leisure monotonous. However, there were some positive impacts of reduced leisure, such as a greater appreciation for what was once a regular activity. This research empowered the voice of children, so their distinct experiences were made visible to those who aim to support their wellbeing. Findings suggest that the promotion of leisure activities in the current climate could mitigate poor wellbeing among children associated with the Covid-19 pandemic
The shifting media discourse surrounding head injuries in association football
Until recently, there has been a lack of significance placed on concussion in association football, particularly in mainstream media coverage. Contemporary incidents and research show that traumatic brain injuries, which may result in neurodegenerative disease, are common in football, but remain poorly understood. However, following the deaths of several heroised FIFA World Cup-winning footballers, as well as a serious head injury to two players in 2020, a noticeable shift in media attitudes towards concussion and head injuries in sport has been detected
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