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Design of a new synthetic nanocatalyst resulting high fuel quality based on multiple supports: experimental investigation and modeling
Get PDFYesIn order to meet the environmental legislations related to sulfur content, it is important to find an alternative techniques for deep removal of sulfur components from fuels. So, in this study, a novel nano-catalyst based on iron oxide (Fe2O3) as active component prepared over composite support (γ-Alumina + HY-zeolite) is developed here for efficient removal of sulfur compounds from fuel via oxidation process. The precipitation method is employed first to prepare the composite support and then the impregnation method is utilized to generate a novel synthetic homemade (Fe2O3/ composite support) nanocatalysts that has not been developed in the literature (iron oxide over composite support). The characterizations of the prepared catalysts display that the surface area of the catalyst increases with increasing the amount of Y-zeolite in composite support. The effectiveness of the catalysts is tested by utilizing oxidative desulfurization (ODS) operation under several operating conditions. The results of the experimental work show that the activity of oxidative desulfurization enhances with increasing Y-zeolite, temperature, and batch time under moderate operating conditions. The oxidative desulfurization efficiency followed the order: CAT-1 < CAT-2 < CAT-3. The CAT-3 performed the high removal of sulfur compounds (90.73%) at 100 min and 423 K. The best values of the kinetic parameters of the ODS process are then determined based on experimental data and model based techniques within gPROMS package. Finally, the reactor model is used to determine the optimal operating conditions while maximizing the removal of sulfur compounds leading to cleaner fuel. Where, 99.3% of the sulfur removal has achieved at batch time of 190.6 min, temperature of 543.56 K and initial sulfur content at 0.8668 wt% in the presence of CAT-3 based on the optimal kinetic parameters (order of reaction (n) of 1.9865719, activation energy (EA) at 29.942 KJ/mol and pre-exponential factor (ko) with 622.926 wt-0.9865719. min-1)
Analysis of gyrobianisotropic media effect on the input impedance, field distribution and mutual coupling of a printed dipole antenna
Get PDFYesIn this paper, we present an analytical study for the investigation of the effects of the magnetoelectric elements of a reciprocal and nonreciprocal bianisotropic grounded substrate on the input impedance, resonant length of a dipole antenna as well as on the mutual coupling between two element printed dipole array in three configuration geometries: broadside, collinear and echelon printed on the same material. This study examines also the effect of the considered bianisotropic medium on the electric and magnetic field distributions that has been less addressed in the literature for antenna structures. Computations are based on the numerical resolution, using the spectral method of moments, of the integral equation developed through the mathematical derivation of the appropriate spectral Green’s functions of the studied dipole configuration. Original results, for chiral, achiral, Tellegen and general bi-anisotropic media, are obtained and discussed with the electric and magnetic field distributions for a better understanding and interpretation. These interesting results can serve as a stepping stone for further works to attract more attention to the reciprocal and non-reciprocal Tellgen media in-depth studies
Mothers’ and fathers’ views on the importance of play for their children’s development: gender differences, academic activities, and the parental role
Get PDFYesBackground: Play is a main driver of children’s cognitive and social development and is crucial for educational success (Ginsburg, 2007). In recent years however, parents and schools are under pressure to prioritise academic targets over play. Aims: The current research investigated parents’ views about three aspects of their children’s play and academic activities. Sample: Predominantly highly educated UK parents (109 mothers and 49fathers) were recruited via social media. Method: Participants were asked to complete an amended online version of the Preschool Play and Learning Questionnaire (Parmar, Harkness, & Super, 2004). The questionnaire consisted of 25 items covering three themes: the importance of play for children’s development, the importance of academic activities, and the importance of parents’ role in their children’s development. The independent variables were the gender of the parent, the gender of their child, and the age group of their child (4 to 7 years, or 8 to 11 years). Results: Parents rated play higher than academic activities or their own roles, but the difference was not noteworthy. However, fathers rated academic activities and the parents’ role significantly higher than mothers did. In addition, parents of girls rated academic activities and their own role, significantly higher than parents of boys.
Conclusions: The findings of the current research highlight gender divisions between parents and towards boys and girls regarding the importance of education. Gender roles appear to influence the way parents think about the academic activities their children partake in
The impact of industrialization on malignant neoplastic disease of bone in England: a study of medieval and industrial samples
Get PDFYesObjective: The increasing prevalence of malignant disease has been associated with shifts in environmental, socioeconomic, and lifestyle risk factors as well as increased adult lifespan. We examine the relationship between malignant neoplasms affecting bone, age and industrialization.
Materials: Pre-existing skeletal data from 11 medieval (1066-1547, n=8,973) and 14 industrial (1700-1890, n=4,748) cemeteries (N=13,721) from England.
Methods: Context number, sex, age-at-death, evidence of skeletal malignancy, and diagnosis were collated. The data were compared using chi square, Kolmogorov-Smirnov tests and logistic regression (α=0.01).
Results: There was a statistically significant increase in skeletal malignancy from 0.06% in the medieval sample to 0.36) in the industrial sample (p< 0.001). Age had a strong relationship with malignancy (p = 0.003), sex did not (p = 0.464). Logistic regression revealed that time-period (p < 0.001) was a stronger predictor of skeletal malignancy than age-at-death (p = 0.002).
Conclusion: Our results confirm that even with the temporal increase in adult human lifespan the increase of malignant neoplasms of bone between the medieval and industrial time periods is still statistically significant.
Significance: The augmented exposure to carcinogens and pollution during the Industrial Revolution had a strong effect on an individual’s susceptibility to developing malignant disease of bone.
Limitations: This meta-analysis relies upon previously gathered data and diagnosis from a large number of researchers and did not include radiographic or CT screening. Only malignant neoplasms that affected bone could be included.
Suggestions for further research: Increasing excavation and analysis of post-medieval cemeteries will provide more data. Multimethod approaches (radiography, CT, Micro-CT and histology) are encouraged
Effect of mixing elements on granule formation in hot melt twin screw granulation
Get PDFYesTwin screw granulation (TSG) has been applied to wet granulation, although its application in melt granulation has been more limited. This work explores potential advantages of hot melt granulation using twin screw extrusion. Four main operating and formulation parameters were investigated: screw speed, number of mixing elements, temperature, and binder percentage. Combinations of these factors were then studied to determine their impact on the quantity and characteristics of granules within the desired size range of 125 - 1000 µm. A screening design of experiments (DOE) study was used with each factor set at three levels, to investigate individual factor effects and interactions. Two types of mixing elements were studied: kneading block (KB) and chaotic elements. The type and number of mixing elements were found to be paramount in contributing to the quantity and characteristics of granules formed. Results obtained agreed with previous findings in literature on the influence of different screw elements on the characteristics of granules formed by twin screw granulation. Additionally, the study revealed the unique impact which different mixer elements have on both granule production and characteristics. Depending on the specific need or use of granules in required applications, the granulation process can be effectively designed to meet the end product quality and outcome.Twin screw granulation (TSG) has been applied to wet granulation, although its application in melt granulation has been more limited. This work explores potential advantages of hot melt granulation using twin screw extrusion. Four main operating and formulation parameters were investigated: screw speed, number of mixing elements, temperature, and binder percentage. Combinations of these factors were then studied to determine their impact on the quantity and characteristics of granules within the desired size range of 125 - 1000 µm. A screening design of experiments (DOE) study was used with each factor set at three levels, to investigate individual factor effects and interactions. Two types of mixing elements were studied: kneading block (KB) and chaotic elements. The type and number of mixing elements were found to be paramount in contributing to the quantity and characteristics of granules formed. Results obtained agreed with previous findings in literature on the influence of different screw elements on the characteristics of granules formed by twin screw granulation. Additionally, the study revealed the unique impact which different mixer elements have on both granule production and characteristics. Depending on the specific need or use of granules in required applications, the granulation process can be effectively designed to meet the end product quality and outcome
Reduction of scour around circular piers using collars
Get PDFYesRiver dynamics and sediment transport play an important role in river bed
morphology. Building a bridge pier along the river alters the cross-section of
the river and causes the change in flow processes. These changes are mainly
responsible for pier scour. In this paper, the usage of collars to reduce scour
around circular piers has been investigated. The collars with different diameters and depth positions have been studied using previous data and additional
data collected in the present study to assess their effectiveness in reducing
scour. Using a wide range of measured data, an empirical equation to compute
the maximum scour depth around the circular piers in the presence of collars
has been proposed. The proposed equation has been validated and proven to
be applicable to a wide range of pier layouts. It has been found that the maximum efficiency can be achieved by fixing the collar at bed level and adopting a
collar diameter 1.5–2.5 times of pier diameter
Exploring the obesity concerns of British Pakistani women living in deprived inner-city areas: A qualitative study
Get PDFYesBritish South Asians have a higher prevalence of overweight and obesity than the wider population. Bradford (UK), with its high Pakistani presence and levels of economic deprivation, has exceptionally high instances, especially in deprived areas where many Pakistanis reside. British Pakistani women in Bradford are more likely to be overweight and obese. There is uncertainty on how these women can be aided to manage their weight. Therefore, the objective of this study was to explore the obesity concerns of Pakistani women living in deprived inner-city areas of Bradford.
Three focus groups interviews were carried out with 23 Pakistani women living in deprived areas of Bradford. Data were analysed thematically.
This exploratory study identified a wide range of concerns that women had around managing their weight. Participants disclosed distrust in information given around medication, conflicting dietary information and reported low levels of trust in women-only organized physical activities. Cultural barriers were identified, which included the gender role of the woman, the lack of culturally appropriate dietary advice, cultural misunderstandings of what constitutes a healthy diet and healthy weight, the lack of culturally suitable exercise facilities and conforming to family and community expectations. Other concerns were language barriers around a lack of understanding, the inability to read Urdu and reliance on others to translate information.
These findings have implications for researchers, local authorities, policy makers and others with an interest in reducing the rates of obesity in this population. Recommendations include training health practitioners to be culturally aware of the diet and eating practices of this community, exploring different ways to support socially isolated women to be more physically active at home, addressing physical activity and diet misconceptions and designing obesity management information materials appropriate for a range of literacy levels.
Public contributors were involved in the development of the interview guide and design of the research. A pilot focus group with participants not included in the present paper was used to help test and refine the focus group questions. Interview transcripts were member checked by participants, and participants assisted with data analysis.UKPRP. Grant Number: MR/S037527/1 NIHR. Grant Number: NIHR20016
Wireless electromagnetic radiation assessment based on the specific absorption rate (SAR): A review case study
Get PDFYesEmploying electromagnetic fields EMFs) in new wireless communication and sensing technologies has substantially increased the level of human exposure to EMF waves. This paper presents a useful insight into the interaction of electromagnetic fields with biological media that is defined by the heat generation due to induced currents and dielectric loss. The specific absorption
rate (SAR) defines the heating amount in a biological medium that is irradiated by an electromagnetic field value. The paper reviews the radio frequency hazards due to the SAR based on various safety standards and organisations, including a detailed investigation of previously published work in terms of modelling and measurements. It also summarises the most common techniques utilised
between 1978 and 2021, in terms of the operational frequency spectrum, bandwidth, and SAR values.The European Union’s Horizon 2020 innovation programme under grant agreement H2020- MSCA-ITN-2016 SECRET-722424 and the U.K. Engineering and Physical Sciences Research Council (EPSRC) under grant EP/E022936/1 supported this research. This study is also sponsored by the FCT/MEC through national funds and, where applicable, co-financed by the ERDF under the PT2020 Partnership Agreement under the UID/EEA/50008/2020 project. This study is part of the POSITIONII project, which is funded by the European Commission’s Joint Undertaking under the grant number Ecsel-7831132-Postitio-II-2017-IA. Moreover, this paper is also partially funded by British Council “2019 UK-China-BRI Countries Partnership Initiative” programme, with project titled “Adapting to Industry 4.0 oriented International Education and Research Collaboration”. In addition, this project has received funding from Universidad Carlos III de Madrid and the European Union’s Horizon 2020 research and innovation program under the Marie Sklodowska-Curie Grant 801538
Democracy under God: Constitutions, Islam and Human Rights in the Muslim World
No full textNoThe place of Islam in constitutions invites fierce debate from scholars and politicians alike. Many of these debates assume an inherent conflict between constitutional Islam and 'secular' values of liberal democracy and human rights. Using case studies from several Muslim-majority states, this book surveys the history and role of Islam in constitutions. Tracing the origins of constitutional Islam, Dawood Ahmed and Muhammad Zubair Abbasi argue that colonial history and political bargaining were pivotal factors in determining whether a country adopted Islam, and not secularism, in its constitution. Contrary to the common contention that the constitutional incorporation of Islam is generally antithetical to human rights, Ahmed and Abbasi show not only that Islam has been popularly demanded and introduced into constitutions during periods of 'democratization' and 'modernization' but also that constitutional Islamization has frequently been accompanied by an expansion in constitutional human rights