2,391 research outputs found
What Motivates Staff to Work at a Therapeutic School for Children Identified as Having Social, Emotional and Behavioural Difficulties?
Those who work at schools with children identified as having social, emotional and behavioural difficulties (SEBD), work in considerably challenging, stressful and undesirable environments (Shuttleworth, 2005). Taking this into consideration, this study focuses on staff motivation, in an attempt to pinpoint what motivates individuals to pursue and commit to a career in this field of work.
Staff members working with children identified as having SEBD at a therapeutic primary school in the UK were interviewed (N = 7). Semi-structured interviews were prepared and carried out inside the school premises in a private space. Interviews were recorded using an audio recorder and were analysed using thematic analysis (Braun & Clarke, 2006). Self-determination theory (Ryan & Deci, 2000) was applied to the data and referred to as a framework.
Five key themes were developed from the data, three of the key themes were deemed to be most relevant to the research question: ‘What motivates staff to work at a therapeutic school for children identified as having emotional and behavioural difficulties?’ These were:
Emotional connection: Occasions when participants spoke of feeling deeply connected to others. This connection was either with children through relatedness, or with colleagues (team spirit).
A sense of feeling good: This was summarised as pride, enjoyment, appreciation, a sense of feeling right/suited, feeling valued, and even ‘the challenge’ and ‘hard work’.
Responsibility: Participants felt driven by a sense of responsibility, for example comparisons were made to being like parent-figures to the children.
These three themes were considered to be the key forms of motivation identified from this particular sample of staff members
Accurate simulation estimates of phase behaviour in ternary mixtures with prescribed composition
This paper describes an isobaric semi-grand canonical ensemble Monte Carlo
scheme for the accurate study of phase behaviour in ternary fluid mixtures
under the experimentally relevant conditions of prescribed pressure,
temperature and overall composition. It is shown how to tune the relative
chemical potentials of the individual components to target some requisite
overall composition and how, in regions of phase coexistence, to extract
accurate estimates for the compositions and phase fractions of individual
coexisting phases. The method is illustrated by tracking a path through the
composition space of a model ternary Lennard-Jones mixture.Comment: 6 pages, 3 figure
Effects of Confinement on Critical Adsorption: Absence of Critical Depletion for Fluids in Slit Pores
The adsorption of a near-critical fluid confined in a slit pore is
investigated by means of density functional theory and by Monte Carlo
simulation for a Lennard-Jones fluid. Our work was stimulated by recent
experiments for SF_6 adsorbed in a mesoporous glass which showed the striking
phenomenon of critical depletion, i.e. the adsorption excess "Gamma" first
increases but then decreases very rapidly to negative values as the bulk
critical temperature T_c is approached from above along near-critical
isochores. By contrast, our density functional and simulation results, for a
range of strongly attractive wall-fluid potentials, show Gamma monotonically
increasing and eventually saturating as the temperature is lowered towards T_c
along both the critical (rho=rho_c) and sub-critical isochores (rho<\rho_c).
Such behaviour results from the increasingly slow decay of the density profile
away from the walls, into the middle of the slit, as T->T_c. For rho < rho_c we
find that in the fluid the effective bulk field, which is negative and which
favours desorption, is insufficient to dominate the effects of the surface
fields which favour adsorption. We compare this situation with earlier results
for the lattice gas model with a constant (negative) bulk field where critical
depletion was found. Qualitatively different behaviour of the density profiles
and adsorption is found in simulations for intermediate and weakly attractive
wall-fluid potentials but in no case do we observe the critical depletion found
in experiments. We conclude that the latter cannot be accounted for by a single
pore model.Comment: 21 pages Revtex. Submitted to Phys. Rev.
Effects of weak surface fields on the density profiles and adsorption of a confined fluid near bulk criticality
The density profile and Gibbs adsorption of a near-critical fluid confined
between two identical planar walls is studied by means of
Monte Carlo simulation and by density functional theory for a Lennard-Jones
fluid. By reducing the strength of wall-fluid interactions relative to
fluid-fluid interactions we observe a crossover from behaviour characteristic
of the normal surface universality class, strong critical adsorption, to
behaviour characteristic of a 'neutral' wall. The crossover is reminiscent of
that which occurs near the ordinary surface transition in Ising films subject
to vanishing surface fields. For the 'neutral' wall the density profile, away
from the walls, is almost constant throughout the slit capillary and gives rise
to an adsorption that is constant along the critical isochore. The same
'neutral' wall yields a line of capillary coexistence that is almost identical
to the bulk coexistence line. In the crossover regime we observe features in
the density profile similar to those found in the magnetisation profile of the
critical Ising film subject to weak surface fields, namely two smooth maxima,
located away from the walls, which merge into a single maximum at midpoint as
the strength of the wall-fluid interaction is reduced or as the distance
between walls is decreased. We discuss similarities and differences between the
surface critical behaviour of fluids and of Ising magnets.Comment: 34 pages, 10 figures, submitted to the Journ. Chem. Phy
Enthalpies of formation of lanthanide oxyapatite phases
A family of lanthanide silicates adopts an oxyapatite-like structure with structural formula Ln9.33∎0.67(SiO4)6O2 (Ln 4 La, Sm, Nd, Gd, ∎ = vacancy). The enthalpies of solution, DHS, for these materials and their corresponding binary oxides were determined by high-temperature oxide melt solution calorimetry using molten 2PbO·B2O3 at 1078 K. These data were used to complete thermodynamic cycles to calculate
enthalpies of formation from the oxides, ΔHs f-oxides (kJ/mol): La9.33∎0.67(SiO4)6O2 = −776.3 ± 17.9, Nd9.33∎0.67(SiO4)6O2 = −760.4 ± 31.9, Sm9.33∎0.67(SiO4)6O2 = −590.3 ± 18.6, and Gd9.33∎0.67(SiO4)6O2 = −446.9 ± 21.9. Reference data were used to calculate the standard enthalpies of formation from the elements, ΔH0 f (kJ/mol): La9.33∎0.67(SiO4)6O2 = −14611.0 ± 19.4, Nd9.33∎0.67(SiO4)6O2 = −14661.5 ± 32.2, Sm9.33∎0.67(SiO4)6O2 = −14561.7 ± 20.8, and Gd9.33∎0.67(SiO4)6O2 = −14402.7 ± 28.2. The formation enthalpies become more endothermic as the ionic radius of the lanthanide ion decreases
Freezing line of the Lennard-Jones fluid: a Phase Switch Monte Carlo study
We report a Phase Switch Monte Carlo (PSMC) method study of the freezing line
of the Lennard-Jones (LJ) fluid. Our work generalizes to soft potentials the
original application of the method to hard sphere freezing, and builds on a
previous PSMC study of the LJ system by Errington (J. Chem. Phys. {\bf 120},
3130 (2004)). The latter work is extended by tracing a large section of the
Lennard-Jones freezing curve, the results for which we compare to a previous
Gibbs-Duhem integration study. Additionally we provide new background regarding
the statistical mechanical basis of the PSMC method and extensive
implementation details.Comment: 18 pages, 6 figure
Metastable liquid-liquid coexistence and density anomalies in a core-softened fluid
Linearly-sloped or `ramp' potentials belong to a class of core-softened
models which possess a liquid-liquid critical point (LLCP) in addition to the
usual liquid-gas critical point. Furthermore they exhibit thermodynamic
anomalies in the density and compressibility, the nature of which may be akin
to those occurring in water. Previous simulation studies of ramp potentials
have focused on just one functional form, for which the LLCP is
thermodynamically stable. In this work we construct a series of ramp
potentials, which interpolate between this previously studied form and a
ramp-based approximation to the Lennard-Jones (LJ) potential. By means of Monte
Carlo simulation, we locate the LLCP, the first order high density liquid
(HDL)-low density liquid (LDL) coexistence line, and the line of density maxima
for a selection of potentials in the series. We observe that as the LJ limit is
approached, the LLCP becomes metastable with respect to freezing into a
hexagonal close packed crystalline solid. The qualitative nature of the phase
behaviour in this regime shows a remarkable resemblance to that seen in
simulation studies of accurate water models. Specifically, the density of the
liquid phase exceeds that of the solid; the gradient of the metastable LDL-HDL
line is negative in the pressure (p)-temperature (T) plane; while the line of
density maxima in the p-T plane has a shape similar to that seen in water and
extends well into the {\em stable} liquid region of the phase diagram. As such,
our results lend weight to the `second critical point' hypothesis as an
explanation for the anomalous behaviour of water.Comment: 7 pages, 8 figure
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