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A study of the vapour phase pyrolysis and alkaline hydrolysis of chloroform
This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University.The decomposition of chloroform at 510ËšC was investigated in a continuous flow system, using nitrogen as the carrier gas. The main products of the reaction were hydrogen chloride, tetrachloroethylene, pentachloroethane and hexachloroethane; hydrogen and chlorine could not be detected. Neither the addition of a radical initiator (azobisisobutyroni trile) nor an inhibitor (phenol) affected the breakdown, and so we have rejected the idea that the main reaction mechanism is of a radical nature.
From the results obtained by varying the surface to volume ratio of the reactor, the reaction appeared to be catalysed by the surface of the reactor, but pretreating the tube by steaming, soaking in water or EDTA solution did not affect the pyrolysis. The reaction appeared to be virtually unaltered when a tube made from very pure silica was used.
Kinetic investigations showed that the reaction was first order with respect to chloroform, and exhibited an induction period. Carrying out the reaction in a carbonised tube resulted in a faster reaction, and an increase in the induction period.
To account for the results obtained, a mechanism is suggested which involves the formation of a carbon polymer on the silica reactor. Chloroform could then be adsorbed onto the polymer where reaction could occur. In a carbonised tube a graphite-like carbon structure may begin to take over as the catalyst. The alkaline hydrolysis of chloroform was studied in aqueous 1,4-dioxane (32 % w/v), at 360C. The rate of disappearance of chloroform was followed by gas-liquid chromatography, whilst the sodium hydroxide concentration was determined by titration with dilute hydrochloric acid. The reaction was second order overall, first order with respect to each of the reactants. Data obtained at 25ËšC, 31ËšC, 36ËšC and 41ËšC was used to determine the activation parameters.
Increasing the concentration of dioxane in the solvent decreased the reaction rate. The reaction showed a definite negative salt effect, sodium chloride exhibiting a greater effect than potassium nitrate.
The reaction between deuterochloroform and sodium deuteroxide in deuterium oxide/dioxane was faster than the reaction in the corresponding proton system.
Application of the Yagil approach suggested that the transition state is associated with seven water molecules. This led us to suggest an alternative mechanism for the reaction, involving nucleophilic attack by water on the trichloromethyl anion, formed by loss of a proton from chloroform.
In order to apply the Yagil criterion the hydration number of diolane had to be determined; a value of 2.25 was obtained.Science Research Counci
‘Me juzgo por natural de Madrid’: Vincencio Carducho, theorist and painter of Spain's court capital
More than a guide for painters, Vicente de Carducho's Diálogos de la pintura has long been recognized to promote painting as a liberal art and to advocate for the creation of an academy of painting in seventeenth-century Madrid. But questions of patriotic belonging and prestige are also at stake in this erudite treatise. In his prologue, Carducho prioritizes his allegiance to his adopted city even while acknowledging his debts to his native Florence. The first part of this article argues that the treatise serves to showcase that allegiance as it participates in a project to make the young political capital a great cultural centre. The second part makes the case for Carducho as a practitioner who understood the debt he owed to the visual culture of his adopted homeland while remaining true to the aesthetic principles of his Florentine training. His late depictions of saints in adoration of the crucifix provide a focus for examining a religious sensibility subtly informed by Spanish devotional literature
Shared neural circuits: The connection between social and physical pain
Interpersonal rejection, exclusion, and loss are known to produce painful feelings (Eisenberger, Lieberman, & Williams, 2003), but little is know about the neural network underlying this type of pain. Recent evidence suggests this social pain may have important neural connections with physical pain (Eisenberger et al., 2003). The current literature review explores the connection between social pain and physical pain in neural activity, individual differences (e.g., pain sensitivity), situation appraisal, social support, and pain reducers (e.g., acetaminophen). The review examines the overlapping pain system as an evolutionary adaptation necessary for survival (MacDonald & Leary, 2005). Authentic experiences of social rejection (e.g., bullying) are explored and offer new directions for research (Sansone, Watts & Wiederman, 2013), and opposing evidence supporting a numbing effect of severe social rejection is discussed (Berstein & Claypool, 2012). The review concludes with a synthesis and discussion about why understanding social pain is important
Regaining Consensus on the Reliability of Memory
In the last 20 years, the consensus about memory being essentially reliable has been neglected in favor of an emphasis on the malleability and unreliability of memory and on the public’s supposed unawareness of this. Three claims in particular have underpinned this popular perspective: that the confidence people have in their memory is weakly related to its accuracy, that false memories of fictitious childhood events can be easily implanted, and that the public wrongly sees memory as being like a video camera. New research has clarified that all three claims rest on shaky foundations, suggesting there is no reason to abandon the old consensus about memory being malleable but essentially reliable
On the nature of the transition disk around LkCa 15
We present CARMA 1.3 mm continuum observations of the T Tauri star LkCa
15,which resolve the circumstellar dust continuum emission on angular scales
between 0.2-3 arcsec, corresponding to 28-420 AU at the distance of the star.
The observations resolve the inner gap in the dust emission and reveal an
asymmetric dust distribution in the outer disk. (Abridge) We calculate that 90%
of the dust emission arises from an azimuthally symmetric ring that contains
about 5x10^{-4} M_sun of dust. A low surface-brightness tail that extends to
the northwest out to a radius of about 300 AU contains the remaining 10% of the
observed continuum emission. The ring is modeled with a rather flat surface
density profile between 40 and 120 AU, while the inner cavity is consistent
with either a sharp drop of the 1.3 mm dust optical depth at about 42 AU or a
smooth inward decrease between 3 and 85 AU. (Abridge). Within 40 AU, the
observations constrain the amount of dust between 10^{-6} and 7 Earth masses,
where the minimum and maximum limits are set by the near-IR SED modeling and by
the mm-wave observations of the dust emission respectively. In addition, we
confirm the discrepancy in the outer disk radius inferred from the dust and
gas, which corresponds to 150 AU and 900 AU respectively. We cannot reconcile
this difference by adopting an exponentially tapered surface density profile as
suggested for other systems, but we instead suggest that the gas surface
density in the outer disk decreases less steeply than that predicted by model
fits to the dust continuum emission. The lack of continuum emission at radii
lager than 120 AU suggests a drop of at least a factor of 5 in the dust-to-gas
ratio, or in the dust opacity. We show that a sharp dust opacity drop of this
magnitude is consistent with a radial variation of the grain size distribution
as predicted by existing grain growth models.Comment: Accepted for publication on ApJ, 13 pages, 11 figure
WellBabies Resident Curriculum: Program Plan and Evaluation for Family Medicine Resident Education in Preventive Well-Child Care
Family medicine is a medical specialty which aims to provide comprehensive health care for the individual, family, and community. The American Academy of Family Physicians (AAFP) further defines family medicine in the context of primary care, as serving a role in health promotion, disease prevention, counseling, patient education, and care for acute and chronic illness. Providing medical care and parental guidance for pediatric patients historically has been a large part of family practice. Based on a survey conducted by the AAFP in 2008, 87.9% of family medicine residency graduates participate in pediatric care. Residency programs in family medicine are structured to prepare physicians for future practice in a primary care environment. The Accreditation Council for Graduate Medical Education (ACGME) is responsible for verifying appropriate education at each residency site. The Residency Review Committee, a sub-group of the ACGME, identifies core competencies and skills for each medical specialty. Specifically regarding pediatric care, this committee requires that family medicine residents are trained in the care of neonates and infants in a structured manner through teaching and role modeling by the family medicine faculty. There are certain requirements for the number of months of training in the pediatric inpatient and outpatient settings, but individual residency programs are left to determine the practical details of the training requirements. Residency training can be measured in several ways, including physician knowledge, confidence, or practice of a given skill. In terms of practice level performance, primary care groups in North Carolina are not fully meeting recommendations for pediatric preventive services. Specifically, only 39% of children at the included practices received at least three of the four surveyed preventive services.' To further examine the practice and opinions of physicians, some authors have made comparisons between family medicine and pediatric physicians. In one such study, family medicine physicians were 5.4 times less likely to provide poison prevention counseling to parents. These family physicians cited lack of training as the primary reason for not offering this type of guidance. Aside from traditional pediatric rotations, direct patient care, and didactics, there is no formal curriculum for early childhood preventive care in the University of North Carolina (UNC) Department of Family Medicine at this time. In 2006, Dr. Cristen Page performed a needs assessment for structured pediatric training in the family medicine residency program at UNC. This assessment collected opinions of graduating family medicine residents through a brief survey. The results indicate that a majority of residents are not confident in their outpatient pediatric training and desired an increase in the amount of training they received (data not published). This needs assessment, in light of national requirements and guidelines for residency training, encouraged the development of a new curriculum in well-child care. The WellBabies Resident Curriculum is a program for UNC family medicine residents based on group well-child care. Group well-child care involves bringing several patients together for a medical visit, allowing group discussion of prevention and counseling topics. Several research groups have shown that group visits are an acceptable alternative to traditional individual care. In addition, group visits provide an environment for coverage of a greater number of prevention topics. The WellBabies Resident Curriculum involves focused didactic sessions and role-modeling by family medicine faculty, in addition to instruction in the evidence base for pediatric preventive care. The curriculum is designed to help residents increase their understanding and knowledge of the evidence for common counseling topics and build their confidence for providing such counseling to parents. This paper will present the program description of the WellBabies Resident Curriculum and the associated evaluation plan.Master of Public Healt
Automated feature extraction and spatial organization of seafloor pockmarks, Belfast Bay, Maine, USA
This paper is not subject to U.S. copyright. The definitive version was published in Geomorphology 124 (2010): 55-64, doi:10.1016/j.geomorph.2010.08.009.Seafloor pockmarks occur worldwide and may represent millions of m3 of continental shelf erosion, but few numerical analyses of their morphology and spatial distribution of pockmarks exist. We introduce a quantitative definition of pockmark morphology and, based on this definition, propose a three-step geomorphometric method to identify and extract pockmarks from high-resolution swath bathymetry. We apply this GIS-implemented approach to 25 km2 of bathymetry collected in the Belfast Bay, Maine USA pockmark field. Our model extracted 1767 pockmarks and found a linear pockmark depth-to-diameter ratio for pockmarks field-wide. Mean pockmark depth is 7.6 m and mean diameter is 84.8 m. Pockmark distribution is non-random, and nearly half of the field's pockmarks occur in chains. The most prominent chains are oriented semi-normal to the steepest gradient in Holocene sediment thickness. A descriptive model yields field-wide spatial statistics indicating that pockmarks are distributed in non-random clusters. Results enable quantitative comparison of pockmarks in fields worldwide as well as similar concave features, such as impact craters, dolines, or salt pools
Enhancing the Employability of Humanities Postgraduates: a Students as Academic Partners Project Report
In an increasingly competitive employment market, postgraduates need to demonstrate more than the ‘skills,
knowledge, attitudes and experiences that are closely
associated with the research process’ (Golovushkina &
Milligan, 2013: 199). Yet results indicate that Worcester
postgraduate students remain unaware of the full range of
opportunities that exist alongside postgraduate study, and
how this affects their subsequent employability. This
research, undertaken with humanities post-graduate
students at University of Worcester, aims to contribute to
discussions about how to enhance the employability of
humanities postgraduates through extra-curricular
activities. The project was implemented as a Students
-As-Partners-in-Learning-Project, using action research; the issue was identified, base-line data collected and this resulted in the creation of a postgraduate blog incorporating suggestions of possible opportunitie
s and links to relevant websites for further information. Informed by this research, the student partners then took active roles in the organization of the Women’s History Network National Conference, ‘Home Fronts: Gender, War and Conflict’, hosted at the University of Worcester in September 2014, to broaden their existing skills base and then to connect this involvement to their professional development through a group CV review. The participants’ own experiences of wider engagement can therefore illuminat
e new ways for understanding employability in relation to humanities postgraduate students
Interpreting nature: shifts in the presentation and display of taxidermy in contemporary museums in Northern England
Taxidermy is an organised craft which synthesises preserved animal skins with man-made materials to recreate a resemblance of living animals. As products of a cultural practice, displayed and interpreted in museums for the public, taxidermied animals are material manifestations of contingent value judgements. Despite the now widely held view in museum studies that the meanings of museum objects are constructed through their interpretation and reception, and therefore can have a multiplicity of meanings, many museums today continue to present and interpret taxidermied animals as objective species representatives. Although scientific themes continue to be privileged by many museums which maintain natural science as a discrete discipline, various social, ethical and political themes relating to the environment and to relationships between people have become more pronounced in recently redeveloped museums. Using Leeds City Museum, the Great North Museum: Hancock, and Museums Sheffield: Weston Park as case studies, this thesis investigates these changes to trace wider cultural shifts in politics, ethics, education and science. By analysing the frameworks within which museums and their staff operate, this investigation is concerned with the relationship between discourse and social practice in the form of museum exhibitions as a means of creating knowledge. It highlights how the public understanding of the natural world is more mutable than some of the enduring traditions of science may suggest, and how the discourses on science, and the objects through which they are articulated, are subject to cultural shifts which put their meanings in flux.
This study is both part of, and a response to, an expanding field in museum studies and material culture studies which re-frames taxidermy objects as culturally contingent and therefore reflective of the subject positions of their makers, and the broader contexts of their making. In collating and investigating a diverse collection of archival material, this study recovers some of taxidermy’s histories, and contributes to the historical discourse on the display and interpretation of museum collections
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