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1 – 10 of 321Manikandamaharaj T.S. and Jaffar Ali B.M.
Effective performance of a direct ethanol fuel cell (FC) stack depends on the satisfactory operation of its individual cells where it is always challenging to manage the…
Abstract
Purpose
Effective performance of a direct ethanol fuel cell (FC) stack depends on the satisfactory operation of its individual cells where it is always challenging to manage the temperature gradient, water flow and distribution of reactants. In that, the design of the bipolar fuel flow path plate plays a vital role in achieving the aforementioned parameters. Further, the bipolar plates contribute 80% of the weight and 30%–40% of its total cost. Aim of this study is to enhance the efficiency of fuel to energy conversion and to minimize the overall cost of production.
Design/methodology/approach
The authors have specifically designed, simulated and fabricated a standard 2.5 × 2.5 cm2 active area proton exchange membrane (PEM) FC flow path plate to study the performance by varying the flow fields in a single ladder, double ladder and interdigitated and varying channel geometries, namely, half curve, triangle and rectangle.
Findings
Using the 3D PEMFC model and visualizing the physical and electrochemical processes occurring during the operation of the FCs resulted in a better-performing flow path plate design. It is fabricated by using additive manufacturing technology. In addition, the assembly of the full cell with the designed flow path plate shows about an 11.44% reduction in total weight, which has a significant bearing on its total cost as well as specific energy density in the stack cell.
Originality/value
Simultaneous optimization of multiple flow path parameters being carried out for better performance is the hallmark of this study which resulted in enhanced energy density and reduced cost of device production.
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Abstract
Levels of the selected major and minor elements (Na, K, Ca, Mg, Ni, Cr, Cd, Pb, Zn and Fe) in 11 summer fruits grown in Pakistan were estimated by the flame AAS method based on HNO3/HClO4 wet‐digestion method. The metal concentrations are expressed as X for triplicate sub‐samples with a standard deviation of ±1.0‐1.5 per cent. Of all the minor elements analyzed, Fe was found to be the dominant metal on mean basis as compared with other metals in fruits, its concentration being 14.25mg/kg. The increasing order of minor‐element concentration was: Cd<Pb<Zn<Cr<Ni<Fe. While for major elements, K concentration was found to be maximum as 409.7mg/kg and increasing order was: Ca<Na<Mg<K. In general, minor‐element concentrations were found to surpass the safe limit laid down by the World Health Organization. Fruits were found to be a rich resource of major elements.
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Levels of selected essential and non‐essential metals (Cd, Cr, Pb, Cu, Fe and Zn) and those of macro‐nutrients (Ca, K, Mg and Na) are estimated in 15 different seasonal fruits…
Abstract
Levels of selected essential and non‐essential metals (Cd, Cr, Pb, Cu, Fe and Zn) and those of macro‐nutrients (Ca, K, Mg and Na) are estimated in 15 different seasonal fruits available in local Pakistan markets. The wet digestion oxidation method was used for the analysis of samples by the flame atomic absorption technique. The results indicated almost 100 percent incidence of occurrence of trace metals and macro‐nutrients in all fruits. The highest concentration was observed for zinc, ranging between 0.13 and 79.9mg/kg, wet weight, respectively for banana and mango. The iron levels ranged from 0.55 to 44.8mg/kg, wet weight, for pomegranate and mango. The concentrations of Cd, Cr, Pb and Cu remained at marginal levels, except for certain fruits where the concentrations were very high. The data are compared with allowed safe limits laid down by WHO.
M. Jaffar, Munir H. Shah, N. Shaheen, A. Khaliq, Saadia R. Tariq, S. Manzoor and M. Saqib
Levels of 12 metals (Ca, K, Na, Mg, Cu, Fe, Mn, Zn, Cd, Cr, Pb and Ni) were estimated in 19 different imported brands of unexpired and expired canned dry milk available from local…
Abstract
Levels of 12 metals (Ca, K, Na, Mg, Cu, Fe, Mn, Zn, Cd, Cr, Pb and Ni) were estimated in 19 different imported brands of unexpired and expired canned dry milk available from local markets. The HNO3/HClO4‐based wet digestion method was used for the analysis of the samples by the FAAS technique under optimum analytical conditions. Of the macronutrients, Ca showed highest at 1,144 μg/g in the dry milk from Holland. In the case of micronutrients, Fe showed the maximum level at 119.15 μg/kg in the milk from UK. Cr dominated at 23.19 μg/kg compared with other heavy toxic trace elements. The following order of decreasing concentration was observed for both unexpired and expired milk: Ca > Na > K > Mg > Fe > Zn > Cr > Pb > Cu > Ni > Cd. All the trace elements were found to have 100 per cent incidence of occurrence. The expired milk samples showed enhanced levels of Fe, Zn, Cr and Pb by a factor of 1.2‐1.6 on average. The results of the metal contents were compared with those for fresh cow milk. The data were statistically evaluated to find bivariate correlation between the metals in pre‐ and post‐expiry milks.
Munir H. Shah, M. Jaffar, N. Shaheen and N. Rasool
This paper seeks to apply an improved electrometric method using polarized electrodes to quantify iodine in 241 salt samples pertaining to 15 different brands procured from the…
Abstract
Purpose
This paper seeks to apply an improved electrometric method using polarized electrodes to quantify iodine in 241 salt samples pertaining to 15 different brands procured from the local market.Design/methodology/approach – Comparative evaluation of the method is made with the iodometric titration and the colorimetric methods.
Findings
The results obtained reveal that the electrometric method excels in attaining higher level of accuracy, precision and lower detection limit, backed by ease of operation.
Practical implications
The method warrants reproducible results both for replicate synthetic and market samples, with a lower detection limit of about 0.1ppm within an acceptable limit of error.
Originality/value
The study shows significant difference between the estimated and labelled iodine values in various brands of iodized salts. Most of the salt samples analysed contain iodine levels far exceeding the WHO permitted limit. The method has the potential of application for in‐situ iodine measurement in iodine fortified salts to ensure rapid quality control, both at the retailer and production levels.
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K. Chandrasekar and R.R. Krishnamurthy
History has taught us that every aspect of the world around us is changing. Right from its formation, the earth has been evolving climatically, edaphically, and biotically to its…
Abstract
History has taught us that every aspect of the world around us is changing. Right from its formation, the earth has been evolving climatically, edaphically, and biotically to its present state. The forcing for all these changes in the past was natural, and human activities had least influence till the industrial revolution. Since the beginning of the 18th century, human activities associated with the industrial revolution have changed the composition of the atmosphere and thereby having a greater influence on the earth's climate. The use of fossil fuels like coal and oil coupled with deforestation has increased the concentration of heat-trapping “greenhouse gases,” which prevent the heat from the earth escaping to space. Because of this, the very greenhouse gases, which helped sustain life on the earth under normal circumstances, have become detrimental due to its higher concentration. Several models have predicted that the rising concentrations of greenhouse gases produce an increase in the average surface temperature of the earth over time. Rising temperatures may, in turn, produce changes in precipitation patterns, storm severity, and sea level, commonly referred to as “climate change.” The Intergovernmental Panel on Climate Change (IPCC) defines climate change broadly as “any change in climate over time whether due to natural variability or as a result of human activity.” The United Nations Framework Convention on Climate Change (UNFCCC) defines climate change as “a change of climate that is attributed directly or indirectly to human activity, that alters the composition of the global atmosphere, and that is in addition to natural climate variability over comparable time periods.”
Marie Claire Annette Van Hout, Flavia Zalwango, Mathias Akugizibwe, Moreen Namulundu Chaka, Charlotte Bigland, Josephine Birungi, Shabbar Jaffar, Max Bachmann and Jamie Murdoch
Women experience a triple burden of ill-health spanning non-communicable diseases (NCDs), reproductive and maternal health conditions and human immunodeficiency virus (HIV) in…
Abstract
Purpose
Women experience a triple burden of ill-health spanning non-communicable diseases (NCDs), reproductive and maternal health conditions and human immunodeficiency virus (HIV) in sub-Saharan Africa. Whilst there is research on integrated service experiences of women living with HIV (WLHIV) and cancer, little is known regarding those of WLHIV, diabetes and/or hypertension when accessing integrated care. Our research responds to this gap.
Design/methodology/approach
The INTE-AFRICA project conducted a pragmatic parallel arm cluster randomised trial to scale up and evaluate “one-stop” integrated care clinics for HIV-infection, diabetes and hypertension at selected primary care centres in Uganda. A qualitative process evaluation explored and documented patient experiences of integrated care for HIV, diabetes and/or hypertension. In-depth interviews were conducted using a phenomenological approach with six WLHIV with diabetes and/or hypertension accessing a “one stop” clinic. Thematic analysis of narratives revealed five themes: lay health knowledge and alternative medicine, community stigma, experiences of integrated care, navigating personal challenges and health service constraints.
Findings
WLHIV described patient pathways navigating HIV and diabetes/hypertension, with caregiving responsibilities, poverty, travel time and cost and personal ill health impacting on their ability to adhere to multi-morbid integrated treatment. Health service barriers to optimal integrated care included unreliable drug supply for diabetes/hypertension and HIV linked stigma. Comprehensive integrated care is recommended to further consider gender sensitive aspects of care.
Originality/value
This study whilst small scale, provides a unique insight into the lived experience of WLHIV navigating care for HIV and diabetes and/or hypertension, and how a “one stop” integrated care clinic can support them (and their children) in their treatment journeys.
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Syed Alamdar Ali Shah, Bayu Arie Fianto, Batool Imtiaz, Raditya Sukmana and Rafiatul Adlin Hj Mohd Ruslan
The purpose of this paper is to perform Shariah review of Brownian motion that is used for prediction of Islamic stock prices and their volatility.
Abstract
Purpose
The purpose of this paper is to perform Shariah review of Brownian motion that is used for prediction of Islamic stock prices and their volatility.
Design/methodology/approach
It uses the Shariah compliant development model guidelines to review the Brownian motion and its applications.
Findings
The model of Brownian motion does not involve any variable that renders it non-Shariah compliant; neither all applications of Brownian motion are Shariah compliant. Because the model is based on stochastic properties that involve randomness, therefore the issue of gharar takes the utmost important to handle in the applications of the model. The results need to be analyzed strictly in accordance with the Shariah whether they create any element of gharar or uncertainty in case of expected price and volatility estimates.
Research limitations/implications
The research suffers from the limitation that it analyses only one model of physics, i.e. Brownian motion model from Shariah perspective.
Practical implications
The research opens an area for Shariah analysis of results generated from the application of advanced models of physics on matters related to Islamic financial markets.
Originality/value
The originality of this study stems from the fact that to the best of the authors’ knowledge, it is the first study that extends Shariah guidelines into Financial physics for making the foundations of Islamic econophysics.
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Naqeeb Ullah Atal, Mohammad Iranmanesh, Fathyah Hashim and Behzad Foroughi
The purpose of this paper is to investigate the determinants of Muslims’ attitude and intention towards Murabaha financing by considering religiosity as a moderator.
Abstract
Purpose
The purpose of this paper is to investigate the determinants of Muslims’ attitude and intention towards Murabaha financing by considering religiosity as a moderator.
Design/methodology/approach
The data were collected through a survey of 373 Muslims in Afghanistan and were analysed using the partial least squares technique.
Findings
The results showed that social influence and religious obligation have a positive effect on attitude towards Murabaha financing. Furthermore, social influence and attitude have a positive effect on the intention to use Murabaha financing. Religiosity moderates negatively the impact of social influence on attitude towards Murabaha financing.
Practical implications
Managers and marketers of Islamic banks may benefit from the findings of this study, which provide insight into the factors that should be considered to promote Murabaha financing.
Originality/value
The findings contribute to the literature on Islamic financing products by demonstrating the drivers of attitude towards and intention to use Murabaha financing. The study also extends the literature by testing the moderating role of religiosity. Furthermore, the study extends the theory of reasoned action in the context of Islamic financing by introducing religious obligation as a potential driver of attitude and religiosity as a moderator.
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Sayeda Zeenat Maryam, Mian Saqib Mehmood and Chaudhry Abdul Khaliq
Islamic banking (IB) is growing rapidly not only in Islamic countries but also in all over the world. The purpose of this paper is to stumble on the features that have an impact…
Abstract
Purpose
Islamic banking (IB) is growing rapidly not only in Islamic countries but also in all over the world. The purpose of this paper is to stumble on the features that have an impact on Islamic banking adoption (IBA) in case of Pakistan.
Design/methodology/approach
The identification of the factors that affect IBA has made by extending the theory of reasoned action (TRA). However, the conceptual model for this study includes knowledge (K), business support (BS), government support (GS), reputation (Rep), religious obligation (RO), cost-benefit (CB) and social influence (SI) as the independent variables. To test the conceptual framework data were collected through a survey by distributing the 400 questionnaires among users- and non-users of Islamic banks. Multiple regression analysis was applied to test the hypothesis of this study.
Findings
The findings of the study suggest that Rep, CB, RO and SI has a highly significant and positive influence on IBA. On the other hand, K, GS and BS have insignificant influence on IBA. The bottom line of this study suggests that more the ROs will be adopted by Islamic banks, more will be the tendency to adopt it by a bank customer in case of Pakistan.
Research limitations/implications
The generalizability of the findings of this research is limited to IB.
Practical implications
Findings of the study present worthy insight especially for the practitioners to develop significant strategies to bridge the gap between industry and academia in case of IB.
Originality/value
This study is an extension of TRA.
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