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An analysis of varying levels of achievement attained by pupils from rural communities in a consolidated high school.
The potential for nickel in the UK
Nickel is a silvery-white, lustrous metallic element, which belongs to the transition metals and is relatively abundant in the Earth's crust. An area of significant growth for nickel, and as such a driving force in the development of new nickel deposits worldwide, is its use as a cathode material in electric vehicle batteries
The potential for cobalt in the UK
Cobalt is a lustrous, silvery-grey metal with many physical and chemical properties that make it useful in a wide variety of chemical and metallurgical applications. In the UK, cobalt is used in high-performance alloys for the aerospace sector and in the cemented carbide, magnet and special steel industries. Cobalt chemicals are used in the manufacture of batteries, glass and ceramics (Petavratzi et al., 2019). An area of significant demand growth for cobalt, and as such a driving force in the search for new cobalt deposits worldwide, is its use as a cathode material in electric vehicle batteries
Approximate treatment of electron Coulomb distortion in quasielastic (e,e') reactions
In this paper we address the adequacy of various approximate methods of
including Coulomb distortion effects in (e,e') reactions by comparing to an
exact treatment using Dirac-Coulomb distorted waves. In particular, we examine
approximate methods and analyses of (e,e') reactions developed by Traini et al.
using a high energy approximation of the distorted waves and phase shifts due
to Lenz and Rosenfelder. This approximation has been used in the separation of
longitudinal and transverse structure functions in a number of (e,e')
experiments including the newly published 208Pb(e,e') data from Saclay. We find
that the assumptions used by Traini and others are not valid for typical (e,e')
experiments on medium and heavy nuclei, and hence the extracted structure
functions based on this formalism are not reliable. We describe an improved
approximation which is also based on the high energy approximation of Lenz and
Rosenfelder and the analyses of Knoll and compare our results to the Saclay
data. At each step of our analyses we compare our approximate results to the
exact distorted wave results and can therefore quantify the errors made by our
approximations. We find that for light nuclei, we can get an excellent
treatment of Coulomb distortion effects on (e,e') reactions just by using a
good approximation to the distorted waves, but for medium and heavy nuclei
simple additional ad hoc factors need to be included. We describe an explicit
procedure for using our approximate analyses to extract so-called longitudinal
and transverse structure functions from (e,e') reactions in the quasielastic
region.Comment: 30 pages, 8 figures, 16 reference
A review of the potential for rare earth element resources from European red muds: examples from SeydiĆehir, Turkey and Parnassus-Giona, Greece
ArticleRare earth elements (REE) are viewed as âcritical metalsâ due to a complex array of production and political issues, most notably a near monopoly in supply from China. Red mud, the waste product of the Bayer process that produces alumina from bauxite, represents a potential secondary resource of REE. Karst-bauxite deposits represent the ideal source material for REE-enriched red mud as the conditions during formation of the bauxite allow for the retention of REE. The REE pass through the Bayer Process and are concentrated in the waste material. Millions of tonnes of red mud are currently stockpiled in onshore storage facilities across Europe, representing a potential REE resource. Red mud from two case study sites, one in Greece and the other in Turkey, has been found to contain an average of approximately 1 000 ppm total REE, with an enrichment of light over heavy REE. Although this is relatively low grade when compared with typical primary REE deposits (Mountain Pass and Mount Weld up to 80 000 ppm), it is of interest because of the large volumes available, the cost benefits of reprocessing waste, and the low proportion of contained radioactive elements. This work shows that around 12 000 tonnes of REE exist in red mud at the two case study areas alone, with much larger resources existing across Europe as a whole.The research leading to these results has received funding from the European 669 Communityâs Seventh Framework Programme ([FP7/2007-2013]) under Grant 670 Agreement no. 309373
What Does it Take to Reduce Massachusetts Emissions 50% by 2030? Challenges Meeting Climate Goals Under Current Legislation (S.2500)
Executive Summary: To do its part in the global fight against climate change, Massachusetts must achieve net zero greenhouse gas emissions by mid-century, and aggressive intermediate goals are essential to ensure that the state is on track for net zero. Senate bill 2500, âAn Act setting next generation climate policy,â stipulates that 2030 emissions must ânot be less than 50% below the 1990 emissions level.â In 2017, Massachusetts carbon dioxide emissions were 22% below 1990 levels, so the state will need to reduce annual emissions by an additional 28% of 1990 levels by 2030. If enacted, S.2500 would give the state important new tools that would significantly reduce emissions. However, our analysis suggests that additional policies beyond those in S.2500 will likely be necessary to reliably achieve the 2030 goal of cutting emissions in half from 1990 levels.
With no new policies enacted (but not accounting for COVID-19), we estimate that 2030 emissions will be roughly 35% below 1990 levels (Figure 1, BAU). We use a range of policy proposals to approximate the key policies in S.2500: the Transportation and Climate Initiative cap and invest program, a net zero stretch building code, and a moderate carbon price (48 in 2030âroughly similar to one in a recent legislative proposal) in the residential, commercial, and industrial sectors. We use published modeling results to approximate these policies and estimate that they would reduce emissions by an additional 6% below 1990 levels (~41%). This leaves an emissions reductions shortfall of ~9% (or 8 million metric tons of CO2, roughly the equivalent of 1.7 million passenger vehicles) in 2030 (see Fig. 1).
To reach a 50% reduction by 2030, Massachusetts could implement a higher carbon price (e.g. 95 by 2030), which would be possible under S.2500. Some (but not all) models suggest that a higher carbon price alone would be sufficient to reach 50% of 1990 levels by 2030. Another option (not in S.2500) is to enact an ambitious clean electricity standard to reduce electricity emissions. To ensure we reach the 2030 goal, robust policies will be needed in all major sectors of the state\u27s economy, with electricity sector decarbonization particularly important (Fig. 1, Stringent case)
Investigating proximate mechanisms and ultimate functions of memory for emotional events
This thesis is an investigation of the proximate mechanisms and ultimate functions of memory for emotional events. The theoretical basis of this Thesis is that in order to reach a full understanding of a biological phenomenon, it is important that both proximate and ultimate (functional) explanations for that phenomenon are explored. Chapters 2 and 3 present an examination of the proximate mechanisms involved in memory consolidation of emotional events. In Chapter 2, three experiments are presented each testing the hypothesis that stress hormone activation immediately following viewing an emotional event enhances memory for that event. Each of the three experiments failed to find an enhancing effect of stress hormone activation on memory consolidation. Chapter 3 describes an investigation into whether the reduced feedback from the body to the brain, which occurs as a result of total spinal cord transection, diminishes the intensity of emotional experience and therefore impairs memory for emotional events. The results of this investigation revealed no differences between spinal cord transection patients and matched control participants in emotional expressivity, emotional awareness and in memory for emotional material. Chapters 4 and 5 explore how memory and emotion may interact differently for males and females and in manner that facilitates their survival and reproduction. Evolutionary theory argues that males should be more concerned than females about threats to their social status, whereas females should be more concerned about threats to their physical appearance and sexual reputation. Chapter 4 describes two experiments testing whether a) males have enhanced emotional arousal and memory for words implying they are of low social status; b) females have enhanced emotional arousal and memory for words implying they are physically unattractive and sexually untrustworthy. The results of these experiments showed that females had enhanced memory for words relating to physical appearance, and partial evidence that males have 2 enhanced memory for words relating to social status. Chapter 5 tests the evolutionary theory that males should be more emotionally aroused and thus have greater memory for cues relating to sexual infidelity (the thought of their partner having sex with another man), whereas females should be more emotionally aroused and have greater memory for cues to emotional infidelity (the thought of their partner forming a close emotional attachment with another woman). It also examines whether relationship status affects emotional arousal and memory for these cues. The results did not find any support for these hypothesised sex difference in memory. However, those âcurrently in a relationshipâ did show enhanced emotional arousal to cues to sexual infidelity compared to those âcurrently not in a relationshipâ. Chapter 6 presents an investigation concerning the evolutionary hypothesis that individuals tend to have enhanced recognition memory for the faces of deceivers or âliarsâ. This chapter describes a study in which participants viewed a series of short video clips of individuals, half of whom were lying, half telling the truth. Participantsâ memory for the individuals that appeared in the video clips was tested but there was no evidence of enhanced memory for the faces of âliarsâ. Chapter 7 provides a general discussion of the findings of this thesis. The failure to find an enhancing effect of post learning stress hormone activation on memory for emotional material, and the failure to find an impairment in memory for emotional material in people with total spinal cord transection contradict two established views on the proximate mechanisms involved in emotion, and emotions effect of the brain. How these findings relate to the established mainstream views on emotion and memory are discussed. The findings of studies concerning the functional interaction of memory and emotion presented in this thesis are also discussed in relation to previous research.EThOS - Electronic Theses Online ServiceGBUnited Kingdo
The Fornax Spectroscopic Survey I. Survey Strategy and Preliminary Results on the Redshift Distribution of a Complete Sample of Stars and Galaxies
The Fornax Spectroscopic Survey will use the Two degree Field spectrograph
(2dF) of the Anglo-Australian Telescope to obtain spectra for a complete sample
of all 14000 objects with 16.5<=Bj<=19.7 in a 12 square degree area centred on
the Fornax Cluster. By selecting all objects---both stars and
galaxies---independent of morphology, we cover a much larger range of surface
brightness and scale size than previous surveys. In this paper we present
results from the first 2dF field. Redshift distributions and velocity
structures are shown for all observed objects in the direction of Fornax,
including Galactic stars, galaxies in and around the Fornax Cluster, and for
the background galaxy population. The velocity data for the stars show the
contributions from the different Galactic components, plus a small tail to high
velocities. We find no galaxies in the foreground to the cluster in our 2dF
field. The Fornax Cluster is clearly defined kinematically. The mean velocity
from the 26 cluster members having reliable redshifts is 1560+/-80 km/s. They
show a velocity dispersion of 380+/-50 km/s. Large-scale structure can be
traced behind the cluster to a redshift beyond z=0.3. Background compact
galaxies and low surface brightness galaxies are found to follow the general
galaxy distribution.Comment: LaTeX format; uses aa.cls (included). Accepted for publication in
Astronomy and Astrophysic
Induction of labour indications and timing: A systematic analysis of clinical guidelines
Background: There is widespread and some unexplained variation in induction of labour rates between hospitals. Some practice variation may stem from variability in clinical guidelines. This review aimed to identify to what extent induction of labour guidelines provide consistent recommendations in relation to reasons for, and timing of, induction of labour and ascertain whether inconsistencies can be explained by variability guideline quality. Method: We conducted a systematic search of national and international English-language guidelines published between 2008 and 2018. General induction of labour guidelines and condition-specific guidelines containing induction of labour recommendations were searched. Guidelines were reviewed and extracted independently by two reviewers. Guideline quality was assessed using the Appraisal of Guidelines for Research and Evaluation II Instrument. Findings: Forty nine guidelines of varying quality were included. Indications where guidelines had mostly consistent advice included prolonged pregnancy (induction between 41 and 42 weeks), preterm premature rupture of membranes, and term preeclampsia (induction when preeclampsia diagnosed â„37 weeks). Guidelines were also consistent in agreeing on decreased fetal movements and oligohydramnios as valid indications for induction, although timing recommendations were absent or inconsistent. Common indications where there was little consensus on validity and/or timing of induction included gestational diabetes, fetal macrosomia, elevated maternal body mass index, and twin pregnancy. Conclusion: Substantial variation in clinical practice guidelines for indications for induction exists. As guidelines rated of similar quality presented conflicting recommendations, guideline variability was not explained by guideline quality. Guideline variability may partly account for unexplained variation in induction of labour rates
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