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

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

A review of the potential for rare earth element resources from European red muds: examples from Seydişehir, Turkey and Parnassus-Giona, Greece

ArticleRare earth elements (REE) are viewed as ‘critical metals’ 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 Community’s 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, “An Act setting next generation climate policy,” stipulates that 2030 emissions must “not be less than 50% below the 1990 emissions level.” 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 ($29/MT rising to$48 in 2030—roughly 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. $58/MT rising to$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 ‘currently in a relationship’ did show enhanced emotional arousal to cues to sexual infidelity compared to those ‘currently not in a relationship’. Chapter 6 presents an investigation concerning the evolutionary hypothesis that individuals tend to have enhanced recognition memory for the faces of deceivers or ‘liars’. 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. Participants’ memory for the individuals that appeared in the video clips was tested but there was no evidence of enhanced memory for the faces of ‘liars’. 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

Factors driving inequality in prostate cancer survival: a population based study

As cancer control strategies have become more successful, issues around survival have become increasingly important to researchers and policy makers. The aim of this study was to examine the role of a range of clinical and socio-demographic variables in explaining variations in survival after a prostate cancer diagnosis, paying particular attention to the role of healthcare provider(s) i.e. private versus public status. Data were extracted from the National Cancer Registry Ireland, for patients diagnosed with prostate cancer from 1998-2009 (N = 26,183). A series of multivariate Cox and logistic regression models were used to examine the role of healthcare provider and socio-economic status (area-based deprivation) on survival, controlling for age, stage, Gleason grade, marital status and region of residence. Survival was based on all-cause mortality. Older individuals who were treated in a private care setting were more likely to have survived than those who had not, when other factors were controlled for. Differences were evident with respect to marital status, region of residence, clinical stage and Gleason grade. The effect of socio-economic status was modified by healthcare provider, such that risk of death was higher in those men of lower socio-economic status treated by public, but not private providers in the Cox models. The logistic models revealed a socio-economic gradient in risk of death overall; the gradient was larger for those treated by public providers compared to those treated by private providers when controlling for a range of other confounding factors. The role of healthcare provider and socio-economic status in survival of men with prostate cancer may give rise to concerns that warrant further investigation