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This paper aims to conduct numerical simulations to investigate steady-state laminar Rayleigh–Bénard convection of yield stress fluids obeying Bingham model in rectangular cross-sectional cylindrical annular enclosures. In this investigation, axisymmetric simulations have been carried out for nominal Rayleigh number range Ra = 10³ to 10⁵, aspect ratio range AR = 0.25 to 4 (i.e. AR = H/L where H is the enclosure height and L is the difference between outer and inner radii) and normalised inner radius range r_i/L = 0 to 16 (where r_i is internal cylinder radius) for a nominal representative Prandtl number Pr = 500. Both constant wall temperature (CWT) and constant wall heat flux (CWHF) boundary conditions have been considered for differentially heated horizontal walls to analyse the effects of wall boundary condition.

The bi-viscosity Bingham model is used to mimic Bingham fluids for Rayleigh–Bénard convection of Bingham fluids in vertical cylindrical annuli. The conservation equations of mass, momentum and energy have been solved in a coupled manner using the finite volume method where a second-order central differencing scheme is used for the diffusive terms and a second-order up-wind scheme is used for the convective terms. The well-known semi-implicit method for pressure-linked equations algorithm is used for the coupling of the pressure and velocity.

It is found that the convective transport strengthens (weakens) with an increase in Ra (AR) for both Newtonian (i.e. Bn = 0) and Bingham fluids, regardless of the boundary conditions. Moreover, the strength of convection is stronger in the CWT configuration than that is for CWHF boundary condition due to higher temperature difference between horizontal walls for both Newtonian (i.e. Bn = 0) and Bingham fluids. The mean Nusselt number Nūcy does not show a monotonic increase with increasing Ra for AR = 1 and r_i/L = 4 because of the change in flow pattern (i.e. number of convection rolls/cells) in the CWT boundary condition, whereas a monotonic increase of Nūcy with increasing Ra is obtained for the CWHF configuration. In addition, Nūcy increases with increasing r_i/L and asymptotically approaches the corresponding value obtained for rectangular enclosures (r_i/L → ∞) for both CWT and CWHF boundary conditions for large values of r_i/L. It is also found that both the flow pattern and the mean Nusselt number Nūcy are dependent on the initial conditions for Bingham fluid cases, as hysteresis is evident for AR = 1 for both CWT and CWHF boundary conditions.

Finally, the numerical findings have been used to propose a correlation for Nūcy in the range of 0.25 ≤ r_i/L ≤ 16, 0.25 ≤ AR ≤ 2 and 5 × 10⁴ ≤ Ra ≤ 10⁵ for the CWHF configuration.

This paper aims to numerically analyse natural convection of yield stress fluids in rectangular cross-sectional cylindrical annular enclosures. The laminar steady-state simulations have been conducted for a range of different values of normalised internal radius (r_i/L 1/8 to 16, where L is the difference between outer and inner radii); aspect ratio (AR = H/L from 1/8 to 8 where H is the enclosure height); and nominal Rayleigh number (Ra from 10³ to 10⁶) for a single representative value of Prandtl number (Pr is 500).

The Bingham model has been used to mimic the yield stress fluid motion, and numerical simulations have been conducted for both constant wall temperature (CWT) and constant wall heat flux (CWHF) boundary conditions for the vertical side walls. The conservation equations of mass, momentum and energy have been solved in a coupled manner using the finite volume method where a second-order central differencing scheme is used for the diffusive terms and a second-order up-wind scheme is used for the convective terms. The well-known semi-implicit method for pressure-linked equations algorithm is used for the coupling of the pressure and velocity.

It is found that the mean Nusselt number based on the inner periphery Nu¯_i increases (decreases) with an increase in Ra (Bn) due to augmented buoyancy (viscous) forces irrespective of the boundary condition. The ratio of convective to diffusive thermal transport increases with increasing r_i/L for both Newtonian (i.e. Bn = 0) and Bingham fluids regardless of the boundary condition. Moreover, the mean Nusselt number Nu¯_i normalised by the corresponding Nusselt number due to pure conductive transport (i.e. Nu¯_i/(Nu¯_i)_cond) shows a non-monotonic trend with increasing AR in the CWT configuration for a given set of values of Ra, Pr, L_i for both Newtonian (i.e. Bn = 0) and Bingham fluids, whereas Nu¯_i/(Nu¯_i)_cond increases monotonically with increasing AR in the CWHF configuration. The influences of convective thermal transport strengthen while thermal diffusive transport weakens with increasing AR, and these competing effects are responsible for the non-monotonic Nu¯_i/(Nu¯_i)_cond variation with AR in the CWT configuration.

Detailed scaling analysis is utilised to explain the observed influences of Ra, BN, r_i/L and AR, which along with the simulation data has been used to propose correlations for Nu¯_i.

This paper aims to investigate the aspect ratio (AR; ratio of enclosure height:length) dependence of steady-state Rayleigh–Bénard convection of Bingham fluids within rectangular enclosures for both constant wall temperature and constant wall heat flux boundary conditions. A nominal Rayleigh number range 103 ≤ Ra ≤ 10⁵ (Ra defined based on the height) for a single representative value of nominal Prandtl number (i.e. Pr = 500) has been considered for 1/4 ≤ AR ≤ 4.

The bi-viscosity Bingham model is used to mimic Bingham fluids for Rayleigh–Bénard convection of Bingham fluids in rectangular enclosures. The conservation equations of mass, momentum and energy have been solved in a coupled manner using the finite volume method where a second-order central differencing scheme is used for the diffusive terms and a second-order up-wind scheme is used for the convective terms. The well-known semi-implicit method for pressure-linked equations algorithm is used for the coupling of the pressure and velocity.

It has been found that buoyancy-driven flow strengthens with increasing nominal Rayleigh number Ra, but the convective transport weakens with increasing Bingham number Bn, because of additional flow resistance arising from yield stress in Bingham fluids. The relative contribution of thermal conduction (advection) to the total thermal transport strengthens (diminishes) with increasing AR for a given set of values of Ra and Pr for both Newtonian and Bingham fluids for both boundary conditions, and the thermal transport takes place purely because of conduction for tall enclosures.

Correlations for the mean Nusselt number Nu ¯ have been proposed for both boundary conditions for both Newtonian and Bingham fluids using scaling arguments, and the correlations have been demonstrated to predict Nu ¯ obtained from simulation data for 1/4 ≤ AR ≤ 4, 10³ ≤ Ra ≤ 10⁵ and Pr = 500.

In England and Wales, legislation pertaining to hate crime recognizes hostility based on racial identity, religious affiliation, sexual orientation, disability or transgender identity. Discussions abound as to whether this legislation should also recognize hostility based on gender or misogyny. Taking a socio-legal analysis, the chapter examines hate crime, gender-based victimization and misogyny alongside the impact of victim identity construction, access to justice and the international nature of gendered harm. The chapter provides a comprehensive investigation of gender-based victimization in relation to targeted hostility to assess the potential for its inclusion in hate crime legislation in England and Wales.

The purpose of this paper is to highlight an urgent need for new and improved approaches to supporting hate crime victims and tackling hate crime perpetration in the light of escalating levels of hate crime and growing concerns over the effectiveness of existing interventions and support structures.

The paper draws from the authors’ own extensive fieldwork conducted with more than 2,000 victims of hate crime over a series of recent studies. The research was designed to uncover lived experiences of hate crime, to understand the physical and emotional harms suffered by victims and their families, and to identify ways of improving the quality of support offered to victims.

The findings illustrate that current responses to hate crime are hampered by a range of perceived challenges and barriers to justice which exacerbate the harms associated with hate crimes. This includes low levels of public awareness of relevant policies, laws and support services, a lack of meaningful engagement between professionals and marginalised communities and a failure to provide victim-centred criminal justice interventions.

This paper includes a number of recommendations in relation to how scholars, policy makers and professionals can overcome the failings that have been identified, which includes prioritising engagement with diverse communities, improving awareness of hate crime and generating a more comprehensive evidence base on hate crime perpetration.

These themes discussed within this paper are based upon the views and experiences of an extensive sample of hate crime victims, many of whom have never previously shared their stories with researchers, the police or any other support organisations.

Enzymatic desizing using α-amylase is the conventional and eco-friendly method of removing starch based size. Conventionally, enzymes are drained after completion of process; being catalysts, they retain their activity after reaction and need to be reused. Immobilization allows the recovery of enzymes to use them as realistic biocatalyst. This study aims to recover and reuse of α-amylase for desizing of cotton via immobilization.

This paper investigates the application of α-amylase immobilized on Chitosan and Eudragit S-100 for cotton fabric desizing. A commercial α-amylase was immobilized on reversibly soluble-insoluble polymers to work out with inherent problems of heterogeneous reaction media. The immobilization process was optimized for maximum conjugate activity, and immobilized amylases were applied for grey cotton fabric desizing.

The desizing performance of immobilized amylases was evaluated in terms of starch removal and was compared to free enzyme. The immobilized amylases showed adequate desizing efficiency up to four cycles of use and were recovered easily at the end of each cycle. The amylase immobilized on Eudragit is more efficient for a particular concentration than chitosan.

Immobilization associates with insolubility and increased size of enzymes which lead to poor interactions and limited diffusion especially in textiles where enzymes have to act on macromolecular substrates (heterogeneous media). The selection of support materials plays a significant role in this constraint.

The commercial α-amylase was covalently immobilized on smart polymers for cotton fabric desizing. The target was to achieve immobilized amylase with maximum conjugate activity and limited constraints. The reversibly soluble-insoluble polymers support provide easy recovery with efficient desizing results in heterogeneous reaction media.

Numerical simulations have been used to analyse steady-state natural convection of non-Newtonian power-law fluids in a square cross-sectioned cylindrical annular cavity for differentially heated vertical walls for a range of different values of nominal Rayleigh number, nominal Prandtl number and power-law exponent (i.e. 103 < Ra < 106, 102 < Pr < 104 and 0.6 < n < 1.8). The paper aims to discuss these issues.

Analysis is carried out using finite-volume based numerical simulations.

Under the assumption of axisymmetry, it has been shown that the mean Nusselt number on the inner periphery Nu _i increases with decreasing (increasing) power-law exponent (nominal Rayleigh number) due to strengthening of thermal advection. However, Nu _i is observed to be essentially independent of nominal Prandtl number. It has been demonstrated that Nu _i decreases with increasing internal cylinder radius normalised by its height r _i /L before asymptotically approaching the mean Nusselt number for a two-dimensional square enclosure in the limit r _i /L→infinity. By contrast, the mean Nusselt number normalised by the corresponding Nusselt number for pure conductive transport (i.e. Nu _i /Nu _cond ) increases with increasing r _i /L.

A correlation for Nu _i has been proposed based on scaling arguments, which satisfactorily captures the mean Nusselt number obtained from the steady-state axisymmetric simulations.

Graphene, which has abundant availability in nature, is currently under research for its functional applications in the field of textiles. The sp² Hybridized 1-atom-thick planar sheet has been under consideration for its unique electrical, mechanical and thermal properties, but there exists a void for aggregated data on the findings of other co-functional properties attained by the material using graphene oxide (GO) finish. This paper aims to define the techniques of extraction of GO, method of its application on textile material followed by detailed evaluation of the differential functional properties achieved.

The methodology used to explain the multiple functionalities of GO finish have been carried out by starting with the chemistry of graphene and the isolation of GO from graphite, followed by the techniques for its application on the textile along with the study on the induced functional properties that may aid to increase its potential applications.

It has been observed that with the aid of optimization of GO finish, the finish in lieu with the conductive potentialities may further provide with many essential properties such as hydrophobicity, ultraviolet protection and antibacterial property.

The field of research on GO finish is naive and except few properties, many functionalities are still unexplored that may enable its smooth production, handling and expanding its area of application. The agglomeration of scattered findings on the achievable functional properties of GO on various textiles has been achieved in this paper.

This paper aims to study the ability of laccase for decolourisation of reactive dyes in presence and absence of natural and synthetic mediators.

Box–Behnken design was used to optimize the parameters to achieve optimum response value. Preliminary screening using several mediators was performed to evaluate extent of decolourisation for the purpose followed by selection of effective mediators only.

Laccase performs in acidic pH; increase in temperature enhances its activity. Rate of decolourisation depends on laccase and dye concentration, temperature, pH and treatment time. Out of five mediators studied, HBT, BT and VA showed promising results.

Study on decolourisation was conducted for individual dyes. In some cases, dyes are applied in combination which requires further study for authentication of data.

Decolourisation with laccase has been found to be a promising technology in waste water treatment. However, selection of mediator remains a crucial factor.

Reactive dyes are self-hydrolysed over time under natural conditions and extent of decolourisation depends on concentration of dye discharged and time spent. If not decolourised quickly, it imposes restriction on use of river water for irrigation.

In this work, activity of various natural and synthetic mediators alongwith laccase was studied to achieve maximum decolourisation which was not studied earlier.

Disabled women are reported to be between twice and five times more likely to experience sexual violence than non-disabled women or disabled men; when these are hate crimes they compound harms for both victims and communities.

This user-led research explores how disabled and Deaf victims and Survivors most effectively resist the harm and injustice they experience after experiencing disablist hate crime involving rape.

Feminist standpoint methods are employed with reciprocity as central. This small-scale peer research was undertaken with University ethics and supervision over a five year period. Subjects (n=522) consisted of disabled and Deaf victims and Survivors in North of England.

The intersectional nature of violence against disabled women unsettles constructed macro binaries of public/private space violence and the location of disabled women as inherently vulnerable. Findings demonstrate how seizing collective identity can usefully resist re-victimization, tackle the harms after disablist hate crime involving rape and resist the homogenization of both women and disabled people.

The chapter outlines inequalities in disabled people’s human rights and recommends service and policy improvements, as well as informing methods for conducting ethical research.

This is perhaps the first user-led, social model based feminist standpoint research to explore the collective resistance to harm after experiencing disablist hate crime involving rape. It crossed impairment boundaries and included community living, segregated institutions and women who rely on perpetrators for personal assistance. It offers new evidence of how disabled and Deaf victims and Survivors can collectively unsettle the harms of disablist hate crime and rape and achieve justice and safety on a micro level.