494 research outputs found
Twenty-three women officers’ experiences of policing in England: The same old story or a different story?
Our research project was concerned primarily with using a feminist analysis to explore the lived reality of 23 women police officers in England and Wales. We undertook 23 qualitative interviews with our participants and our research straddles four decades of policing practice, which allowed us to explore changes that were seen to have taken place during this period. First, participants discussed their lived reality, which included banter, bullying and harassment for many. Second, and perhaps more surprisingly, at certain times of unrest, riots or threats, some of our participants were provided with opportunities, for example, during the IRA threat, the riot in Toxteth and the miners’ strike. We suggest that examples from our data capture an early disruption of the ‘ideal’ heroic male police officer that Silvestri examines [Silvestri M (2018) Disrupting the ‘heroic’ male within policing: a case of direct entry. Feminist Criminology 13(3): 309–328] whose removal from their normal role during periods of socio-political disorder allowed women officers to leave the gendered division of labour and undertake the heroic police constable role while the men were busy being ‘heroic’ at the source of threat and unrest. We sought to explore changes such as the uniform as a site of protest for some of our officers who challenged an uncomfortable and unfit uniform in the early days, and explained that there were still problems with the kit and design at times. Our findings illustrated that, on the whole, although massive changes had been made, it was a case of the same old story in terms of sexual harassment and banter for female officers and more was required to address these issues, which fits with reviews and studies in both England and Wales and in Australia. Finally, we noted using participants’ words how much many of these women had enjoyed their role within policing in spite of these challenges
Study of mass transfer correlations for intensified absorbers in post-combustion CO2 capture based on chemical absorption
Process intensification (PI) technologies such as rotating packed beds (RPBs) could reduce the size of absorber used
in post-combustion CO2 capture (PCC) based on chemical absorption processes by about 12 times compared to
absorber with standard packed beds. However, mass transfer correlations for predicting effective interfacial area and
liquid film mass transfer coefficient in RPBs are limited in literature and their prediction accuracy against experimental
data is yet to be compared. This need is addressed in this study by evaluating the performances of different correlations
through comparison with experimental data. Of all the correlations assessed, it is found that Lou et al. [1] and Tung
and Mah [2] correlations give reliable estimate of the effective interfacial area and liquid film mass transfer
coefficients respectively
Langevin equations with multiplicative noise: resolution of time discretization ambiguities for equilibrium systems
A Langevin equation with multiplicative noise is an equation schematically of
the form dq/dt = -F(q) + e(q) xi, where e(q) xi is Gaussian white noise whose
amplitude e(q) depends on q itself. Such equations are ambiguous, and depend on
the details of one's convention for discretizing time when solving them. I show
that these ambiguities are uniquely resolved if the system has a known
equilibrium distribution exp[-V(q)/T] and if, at some more fundamental level,
the physics of the system is reversible. I also discuss a simple example where
this happens, which is the small frequency limit of Newton's equation d^2q/dt^2
+ e^2(q) dq/dt = - grad V(q) + e^{-1}(q) xi with noise and a q-dependent
damping term. The resolution does not correspond to simply interpreting naive
continuum equations in a standard convention, such as Stratanovich or Ito. [One
application of Langevin equations with multiplicative noise is to certain
effective theories for hot, non-Abelian plasmas.]Comment: 15 pages, 2 figures [further corrections to Appendix A
Dirac dispersion and non-trivial Berry's phase in three-dimensional semimetal RhSb3
We report observations of magnetoresistance, quantum oscillations and
angle-resolved photoemission in RhSb, a unfilled skutterudite semimetal
with low carrier density. The calculated electronic band structure of RhSb
entails a quantum number in analogy to
strong topological insulators, and inverted linear valence/conduction bands
that touch at discrete points close to the Fermi level, in agreement with
angle-resolved photoemission results. Transport experiments reveal an
unsaturated linear magnetoresistance that approaches a factor of 200 at 60 T
magnetic fields, and quantum oscillations observable up to 150~K that are
consistent with a large Fermi velocity ( ms), high
carrier mobility ( /Vs), and small three dimensional hole pockets
with nontrivial Berry phase. A very small, sample-dependent effective mass that
falls as low as bare masses scales with Fermi velocity, suggesting
RhSb is a new class of zero-gap three-dimensional Dirac semimetal.Comment: 9 pages, 4 figure
Nonextensive Statistical Mechanics Application to Vibrational Dynamics of Protein Folding
The vibrational dynamics of protein folding is analyzed in the framework of
Tsallis thermostatistics. The generalized partition functions, internal
energies, free energies and temperature factor (or Debye-Waller factor) are
calculated. It has also been observed that the temperature factor is dependent
on the non-extensive parameter q which behaves like a scale parameter in the
harmonic oscillator model. As , we also show that these approximations
agree with the result of Gaussian network model.Comment: 8 pages, 2 figure
Study of mass transfer correlations for rotating packed bed columns in the context of solvent-based carbon capture
The application of rotating packed beds (RPBs) in solvent-based carbon capture processes, will greatly reduce the physical footprint, capital and operating cost of the process. However, in designing RPBs, correlations for predicting mass transfer parameters are generally limited in literature and their prediction accuracies have not been demonstrated independently. In this paper, an RPB absorber model was developed in gPROMS ModelBuilder® and used to test and compare different correlations for predicting the effective interfacial area, liquid and gas film mass transfer coefficients. Our results showed that the modified packed column mass transfer correlations where the “g” term (i.e. gravitational acceleration) is replaced with “rw2” (i.e. centrifugal acceleration) commonly used in literature for RPBs generally give poor predictions compared to using correlations developed specifically for RPBs. Also, the Tung and Mah correlation has better predictive accuracy for the liquid film mass transfer coefficient in RPBs than more complex correlations. Finally, a set of new data for the gas film mass transfer coefficient for RPBs were also derived from overall volumetric mass transfer coefficient (KGa) experimental data from literature. This is the first report of gas film mass transfer data for RPBs. The results in this paper will guide researchers in selecting suitable correlations for predicting mass transfer parameters in RPBs
Electronic in-plane symmetry breaking at field-tuned quantum criticality in CeRhIn5
Electronic nematics are exotic states of matter where electronic interactions
break a rotational symmetry of the underlying lattice, in analogy to the
directional alignment without translational order in nematic liquid crystals.
Intriguingly such phases appear in the copper- and iron-based superconductors,
and their role in establishing high-temperature superconductivity remains an
open question. Nematicity may take an active part, cooperating or competing
with superconductivity, or may appear accidentally in such systems. Here we
present experimental evidence for a phase of nematic character in the heavy
fermion superconductor CeRhIn5. We observe a field-induced breaking of the
electronic tetragonal symmetry of in the vicinity of an antiferromagnetic (AFM)
quantum phase transition at Hc~50T. This phase appears in out-of-plane fields
of H*~28T and is characterized by substantial in-plane resistivity anisotropy.
The anisotropy can be aligned by a small in-plane field component, with no
apparent connection to the underlying crystal structure. Furthermore no
anomalies are observed in the magnetic torque, suggesting the absence of
metamagnetic transitions in this field range. These observations are indicative
of an electronic nematic character of the high field state in CeRhIn5. The
appearance of nematic behavior in a phenotypical heavy fermion superconductor
highlights the interrelation of nematicity and unconventional
superconductivity, suggesting nematicity to be a commonality in such materials
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