In this work, we focus on the synthesis of Cu
0.95
Zn
0.05
O and Cu
0.9
Zn
0.05
M
0.05
O (M = Cr, Co, Cd) nanocrystals by employing low-cost sol–gel method. The effect of single doping and co-doping ...on physical, antibacterial, and photocatalytic properties of CuO has been successfully investigated using characterization tools comprising XRD, SEM, FTIR, UV–Vis, and
I
–
V
measurements. X-ray diffraction pattern exhibited that the grown product of CuO has no traces of impurities, indicated the successful incorporation of dopants without changing monoclinic structure. The X-ray peak profile analysis was adopted to calculate the average crystallite size (
D
) by considering the contributions of lattice strain on peak broadening. The calculated direct energy bandgap indicated redshift (1.26 eV to 1.81) eV by co-doping. The
I
–
V
study revealed the enhancement in electrical properties by co-doping. The effects of co-doping on photocatalytic properties of CuO were studied by degradation of methylene blue (MB) and methyl orange (MO) dyes under direct sunlight. The Zn/Cd-doped nanocrystal has a higher degradation efficiency 98.4% against MB and 96.1% against MO dye in 50 min. The enhanced photodegradation is due to the generation of reactive species confirmed by scavenger's experiments. The recyclability test showed the reusability of grown catalyst up to the 4th cycle. The antibacterial property was studied against
Staphylococcus aureus
and
Klebsiella pneumoniae
bacterial strains, which showed the highest zone of inhibition 31 mm, and 32 mm for co-doped samples. Furthermore, the present study paves the path to modify the properties of CuO for optoelectronic devices, environmental, and biomedical applications.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Pakistan has 185 billion tonnes reserves of coal but unfortunately the quality of 80% of this coal is not good. As the country has a shortage of energy so it is necessary to refine the coal before it ...can be used to produce electricity. In this sense, this research is very important as it enables indigenous coal to meet the increasing energy demand. This study is focused on the control of sulfur emissions during the combustion of high sulfur Pakistani coal from the Trans Indus Range and the Salt Range. Parameters like Ca/S molar ratios (MRs), limestone particle size, bed temperature, and different percentages of biomass in co-firing with coal have been studied. It is showed that desulfurization of coal was maximum with the fine-sized particles of limestone. Co-firing of moderate quantity biomass exhibited a considerable decrease in SO2 emissions. Results achieved are presented in the form of tables and plots. This study for control of the gaseous emissions from combustion in FBC facility has great potential for new coal based power projects, especially in Pakistan.
In this article, a dynamical model with advection-diffusion, elucidating the transmission process of disease infection type computer virus, is studied. Such kind of systems help to alleviate the ...effects of virus by prior predictions described in the model. The existence and uniqueness of the solutions of the system is investigated. A solution space (Banach space) is considered to make the possibility of existence of the solutions of proposed system. A closed and convex subset is defined in the Banach space, in which the solutions of the coupled system are optimized. The essential explicit estimates for the solutions are also calculated for the corresponding auxiliary data. Moreover, a non-standard finite difference scheme is applied to find the approximate solution of the prescribed problem. For the validity of the proposed scheme, the possession of some important structural properties by the applied numerical technique are presented. These structural properties are consistency and stability. To prove the numerical stability, Von-Neumann criteria is adopted. In the study of such population dynamics type models, positivity is one of the most important physical properties of the numerical scheme that must be preserved. To prove the positivity of the numerical method, a reliable result is established. The validation of the present study is shown by illustrating an example. The behaviors of the state variables are described by plotting the graphs of the associated example.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The novel coronavirus disease, coined as COVID-19, is a murderous and infectious disease initiated from Wuhan, China. This killer disease has taken a large number of lives around the world and its ...dynamics could not be controlled so far. In this article, the spatio-temporal compartmental epidemic model of the novel disease with advection and diffusion process is projected and analyzed. To counteract these types of diseases or restrict their spread, mankind depends upon mathematical modeling and medicine to reduce, alleviate, and anticipate the behavior of disease dynamics. The existence and uniqueness of the solution for the proposed system are investigated. Also, the solution to the considered system is made possible in a well-known functions space. For this purpose, a Banach space of function is chosen and the solutions are optimized in the closed and convex subset of the space. The essential explicit estimates for the solutions are investigated for the associated auxiliary data. The numerical solution and its analysis are the crux of this study. Moreover, the consistency, stability, and positivity are the indispensable and core properties of the compartmental models that a numerical design must possess. To this end, a nonstandard finite difference numerical scheme is developed to find the numerical solutions which preserve the structural properties of the continuous system. The M-matrix theory is applied to prove the positivity of the design. The results for the consistency and stability of the design are also presented in this study. The plausibility of the projected scheme is indicated by an appropriate example. Computer simulations are also exhibited to conclude the results.
In this article, a numerical model for a Brusselator advection–reaction–diffusion (BARD) system by using an elegant numerical scheme is developed. The consistency and stability of the proposed scheme ...is demonstrated. Positivity preserving property of the proposed scheme is also verified. The designed scheme is compared with the two well-known existing classical schemes to validate the certain physical properties of the continuous system. A test problem is also furnished for simulations to support our claim. Prior to computations, the existence and uniqueness of solutions for more generic problems is investigated. In the underlying system, the nonlinearities depend not only on the desired solution but also on the advection term that reflects the pivotal importance of the study.
This paper explores the emerging field of thermo-acoustic devices, specifically focusing on developing robust bidirectional turbines. Amidst growing concerns about climate change, rising energy ...demands, and the urgent need for alternative solutions, the study highlights the underexplored domain of bidirectional turbines within thermo-acoustic systems, offering a crucial pathway toward cleaner and more sustainable technologies, thereby providing commercialization potential. It identifies a significant gap in dedicated investigations regarding the interaction, efficiency, and challenges associated with bidirectional turbines and adopts a comprehensive methodology integrating analytical modelling, computational fluid dynamics simulations, and practical experimentation. An axial bidirectional turbine is carefully selected, designed, and optimized using advanced tools such as MATLAB R2016a and CAD software, including PTC Creo 5.0 and Solidworks 2023. The validity of the CAD model is verified through ANSYS 16.2 CFX simulations, followed by experimental validation to corroborate and enhance theoretical insights. The conclusions drawn from this study offer valuable recommendations for further research and practical implementations.
Continuous inhalation of coal dust among coal workers leads to a variety of disorders. The present study aims to evaluate the potential oxidative stress associated with coal dust generated from coal ...mining activities among exposed workers through the antioxidant enzyme system, including superoxide dismutase (SOD), catalase (CAT), and glutathione (GSH). In this study cohort, intensive coal mine workers were assessed for antioxidant variations. Blood samples were collected from dust-exposed workers (engaged in different activities at coal mines; n = 311) and residents of the same city (nonexposed, control group; n = 50). The workers’ exposure to coal dust was categorized based on working area (administrative group, surface workers, underground workers), working hours (up to 8 h and more than 8 h), and time of service. The results showed significantly altered activities of SOD, CAT, and GSH among the whole exposed group and its categories compared to the control group. A significant difference was also observed between high- and low-exposure groups. Statistical analysis revealed a negative correlation between antioxidant activity (catalase and SOD) and coal dust levels. Besides, coal exposure was associated with the time of service, smoking status, and dietary habits. The findings of this study reveal higher oxidative stress among highly exposed coal mine workers (underground workers > surface workers > administrative group > nonexposed group), and longer working hours have more pronounced adverse effects on workers’ health.
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IJS, KILJ, NUK, PNG, UL, UM, UPUK
In this article, a nonlinear autocatalytic chemical reaction glycolysis model with the appearance of advection and diffusion is proposed. The occurrence and unicity of the solutions in Banach spaces ...are investigated. The solutions to these types of models are obtained by the optimization of the closed and convex subsets of the function space. Explicit estimates of the solutions for the admissible auxiliary data are formulated. An elegant numerical scheme is designed for an autocatalytic chemical reaction model, that is, the glycolysis model. The fundamental traits of the prescribed numerical method, for instance, the positivity, consistency, stability, etc., are also verified. The authenticity of the proposed scheme is ensured by comparing it with two extensively used numerical techniques. A numerical example is presented to observe the graphical behavior of the continuous system by constructing the numerical algorithm. The comparison depicts that the projected numerical design is more productive as compared to the other two schemes, as it holds all the important properties of the continuous model.
Gemini virus coat protein (CP) is an important element of vector specificity and mandatory for insect transmission as well regardless of the type of gemini virus. This study was planned to conduct ...virus acquisition and transmission experiments using screen cages in an insectary for the period of one month. For this purpose non-viruliferous whiteflies (B cryptic species) were reared and used to acquire the viruses for 48-72 h from the agroinfiltered symptomatic tobacco (Nicotiana benthamiana Domin.) and tomato (Solanum lycopersicum L.) plants and these were liberated to healthy plants for transmission of viruses. It was evident from the results that the whiteflies were incapable to acquire and transmit chickpea chlorotic dwarf virus (CpCDV)-a mastrevirus and mastrebegomo chimeric virus (MCV) from the symptomatic tobacco and tomato plants to healthy plants. Whiteflies also failed to acquire and transmit the cotton leaf curl Kokhran virus-Burewala strain (CLCuKoV-Bu)- a begomovirus from infected to healthy tobacco plants due to the inability of whiteflies to feed on Nicotiana benthamiana Domin. leaves. Although whitefly successfully acquired and transmitted the CLCuKoV-Bu from symptomatic tomato leaves to healthy one whose presence later confirmed by DNA extraction from whiteflies and symptomatic plants followed by PCR amplification of CP gene and full length genome of viruses for authentication of results. So, it has been confirmed that whiteflies were not responsible for transmission of CpCDV and MCV from diseased to healthy plants. Keywords: Whiteflies, Geminivirus coat protein, Mastrevirus, Begomovirus, Mastrebegomo chimeric virus
Esterification, a reaction extensively used in chemical processing, is limited by the establishment of kinetic equilibrium, i.e. marginally exer/endergonic. The reaction is generally slow with low ...yield making downstream separation cost intensive. A new heterogeneous contacting method for the synthesis of ethyl acetate through fine bubbles tests the hypothesis that reactive distillation can “pull” the reaction nearer to completion, reducing the downstream separation requirements. It achieves a high yield of ethyl acetate, 79.9% in 35 min, as compared with 64% conversion in 350 min using a conventional method. The kinetics of esterification reaction under bubbly flow conditions are studied – entirely different from the conventional bulk model. The alcohol is fed as vapor within the bubbles which means alcohol is always in deficit, providing an opportunity to convert an equilibrium limited reaction to nearly irreversible one. As the bubbles flow upwards, the reaction proceeds at the “skin” of the bubble. If the esterification reaction occurs at or near the microbubble interface, ethanol is in large excess in the bubble phase, as acetic acid is well below its boiling point in the liquid phase. By Le Chatelier's principle, the local excess ethanol will push the equilibrium towards completion. Similarly, removal of water and ethyl acetate via the “dry” bubble pulls the equilibrium towards completion.
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