A mathematical model for investigation of dry band location on 22 kV bushing with and without RTV coating: Experimental study.

As different pollutants are deposited on the high voltage bushings, a dry band forms, which causes a flashover. The bushing's contaminated layer will weaken its insulation and have an impact on its electrical characteristics. The performance of bushings in dry band conditions of various lengths was investigated in this proposed piece of work, and a dynamic arc model is presented for the arc process in polluted bushings. It shows satisfactory performance in modelling the arc variables for various dry band positions. The developed dynamic open model for contaminated bushings with and without RTV coating predicted the flashover voltage and dry band positions. Any type of contamination, such as sea salt, road salt, and industrial pollutants prevalent in several sites, can be studied using the established model. Ultimately, it was discovered that there was good agreement between the model's results and the outcomes of the experiments. •Mathematical modeling of 22 kV bushing is conceded out for diverse polluted dry band location at lead-in, lead-out and middle region of bushing surface.•Dynamic arc modeling involved in bushing flashover process for different dry band location is done and flashover voltage is predicted•Experimental work is carried out to find FOV for the bushing with different dry location and compared with predicted FOV.

Characterization of new cellulose fiber extracted from second generation Bitter Albizia tree.

The present work examines the physical, thermal tensile, and chemical properties of wood skin fibers obtained from second generation Bitter Albizia (BA) tree skin. Chemical characterization of BA fibers showed the presence of various chemical contents such as cellulose of 74.89 wt. %, hemicellulose of 14.50 wt. %, wax of 0.31 wt. %, lignin of 12.8 wt. %, moisture of 11.71 wt. %, and ash of 19.29 wt. %. The density of BA fibers (BAFs) was showed 1285 kg/m3. XRD analysis of BAFs showed a crystallinity index (CI) of 57.20% and size of crystallite of 1.68 nm. Tensile strength and strain to failure of BAFs examined through tensile test were 513-1226 MPa and 0.8-1.37% respectively. TGA portrayed the thermal steadiness of BAFs as 339 °C with 55.295 kJ/mol kinetic activation energy, its residual mass was 23.35% at 548 °C. BAFs with high CI, less wax content, and better tensile strength make more suitable for making polymer matrix composites. SEM images of the BAFs surface depicted that the fiber outer surface has more rough which shows that they can contribute to hige fiber-matrix adhesion during composites preparation.

Sustainable wastewater treatment by RO and hybrid organic polyamide membrane nanofiltration system for clean environment.

One of the environmental pollution is happened by the discharge of industrial wastewater that needs to be adequately filtered. Given that the effluent from the leather industry contains high levels of chromium, heavy metals, lipids, and Sulphur, it is one of the wastewater disposals that are most damaging. This experimental study focuses on reverse osmosis and hybrid organic polyimide membrane for nanofiltration for sustainable wastewater treatment. In the RO and organic polyamide Nano-porous membranes, a thin film of polyamide membrane was used for efficient filtration. Taguchi analysis optimized process parameters such as pressure, temperature, pH, and volume reduction factor. The outcome shows an 89% reduction in total wastewater hardness, an 88% reduction in sulfate, and an 89% efficiency reduction in COD. As a result, the proposed technology significantly increased filtration efficiency.

A novel investigations on medical and non-medical mask performance with influence of marine waste microplastics (polypropylene).

The entire human race is struggling with the spread of COVID-19. Worldwide, the wearing of face masks is indispensable to prevent such spread. Despite numerous studies reporting on the fabrication of face masks and surgical masks to reduce spread and thus human deaths, this novel work is considered the marine waste of microplastics, namely Polypropylene (PP) polymer, used to fabricate non-woven fabric masks through the melt-blown process. This experimental work aims to maximize the mask's quality and minimize its fabrication cost by optimizing the melt-blown process parameters and using microplastics. The melt-blown process was used to make masks. Parameters such as extruder temperature, hot air temperature, melt flow rate, and die-to-collector distance (DCD) were investigated as independent variables. The quality of the mask was investigated in terms of bacterial filtration efficiency (BFE), particle filtration efficiency (PFE), and differential pressure. The Taguchi L16 orthogonal array and Taguchi analysis were employed for experimental design and statistical optimization, respectively. The results reveal that the higher BFE and PFE are recorded at 96.7 % and 98.6 %, respectively. The surface morphological investigation on different layers ensured the fine and uniform porosity of the layers and exhibited minimum breath resistance (a low differential pressure of 0.00152 kPa/cm2). Hence the chemically treated marine waste microplastics improved the masks' performance.

Performance analysis of biofuel-ethanol blends in diesel engine and its validation with computational fluid dynamics.

The engine tests aimed to produce comparable data for fuel consumption, exhaust emissions, and thermal efficiency. The computational fluid dynamics (CFD) program FLUENT was used to simulate the combustion parameters of a direct injection diesel engine. In-cylinder turbulence is controlled using the RNG k-model. The model's conclusions are validated when the projected p-curve is compared to the observed p-curve. The thermal efficiency of the 50E50B blend (50% ethanol, 50% biofuel) is higher than the other blends as well as diesel. Diesel has lower brake thermal efficiency among the other fuel blends used. The 10E90B mix (10% ethanol, 90% biofuel) has a lower brake-specific fuel consumption (BSFC) than other blends but is slightly higher than diesel. The temperature of the exhaust gas rises for all mixtures as the brake power is increased. CO emissions from 50E50B are lower than diesel at low loads but slightly greater at heavy loads. According to the emission graphs, the 50E50B blend produces less HC than diesel. NOx emission rises with increasing load in the exhaust parameter for all mixes. A 50E50B biofuel-ethanol combination achieves the highest brake thermal efficiency, 33.59%. The BSFC for diesel is 0.254 kg/kW-hr at maximum load, while the BSFC for the 10E90B mix is 0.269 kg/kW-hr, higher than diesel. In comparison to diesel, BSFC has increased by 5.90%.

Fe3O4-multiwalled carbon nanotubes-bentonite as adsorbent for removal of methylene blue from aqueous solutions.

The contamination of water due to present of dyes, poses serious health problems. Therefore, treatment of contaminated water is necessary to resolve this problem. A tailored co-precipitation technique has been successfully used to prepare Fe3O4-multiwalled Carbon Nanotubes (MWCNTs)-Bentonite nanocomposite. The methylene blue present in aqueous solutions was removed using synthesized nanocomposite as adsorbent. The synthesized novel nanocomposite was analyzed by various characterization techniques. The scanning electron microscope analysis shows that Bentonite and Fe3O4 nanoparticles are well decorated with the MWCNTs matrix. The nanocomposite exhibited a high BET surface area of 204.01 m2/g with a pore volume of 0.367 cm3/g. The BJH adsorption average pore diameter was analyzed to be 7.2 nm. Moreover, the adsorption model was in agreement with the Redlich-Peterson model with adsorption capacity of 48.2 mg/g with a high nonlinear regression coefficient (R2 = 0.985) and a low chi-square value (χ2 = 6.18). Kinetics data were described well by pseudo-first-order and pseudo second order, models with a high non-linear regression coefficient (R2 = 0.993). Adsorption of MB dye was determined to be a non-spontaneous and endothermic process since the values of ΔG, and ΔH were positive, and the entropy value was negative. Thus, the synthesized nanocomposite established itself as a promising candidate for the water treatment process.

SARS-CoV-2 removal by mix matrix membrane: A novel application of artificial neural network based simulation in MATLAB for evaluating wastewater reuse risks.

The COVID-19 outbreak led to the discovery of SARS-CoV-2 in sewage; thus, wastewater treatment plants (WWTPs) could have the virus in their effluent. However, whether SARS-CoV-2 is eradicated by sewage treatment is virtually unknown. Specifically, the objectives of this study include (i) determining whether a mixed matrixed membrane (MMM) is able to remove SARS-CoV-2 (polycarbonate (PC)-hydrous manganese oxide (HMO) and PC-silver nanoparticles (Ag-NP)), (ii) comparing filtration performance among different secondary treatment processes, and (iii) evaluating whether artificial neural networks (ANNs) can be employed as performance indicators to reduce SARS-CoV-2 in the treatment of sewage. At Shariati Hospital in Mashhad, Iran, secondary treatment effluent during the outbreak of COVID-19 was collected from a WWTP. There were two PC-Ag-NP and PC-HMO processes at the WWTP targeted. RT-qPCR was employed to detect the presence of SARS-CoV-2 in sewage fractions. For the purposes of determining SARS-CoV-2 prevalence rates in the treated effluent, 10 L of effluent specimens were collected in middle-risk and low-risk treatment MMMs. For PC-HMO, the log reduction value (LRV) for SARS-CoV-2 was 1.3-1 log10 for moderate risk and 0.96-1 log10 for low risk, whereas for PC-Ag-NP, the LRV was 0.99-1.3 log10 for moderate risk and 0.94-0.98 log10 for low risk. MMMs demonstrated the most robust absorption performance during the sampling period, with the least significant LRV recorded in PC-Ag-NP and PC-HMO at 0.94 log10 and 0.96 log10, respectively.

A deep transfer learning-based convolution neural network model for COVID-19 detection using computed tomography scan images for medical applications.

The Coronavirus (COVID-19) has become a critical and extreme epidemic because of its international dissemination. COVID-19 is the world's most serious health, economic, and survival danger. This disease affects not only a single country but the entire planet due to this infectious disease. Illnesses of Covid-19 spread at a much faster rate than usual influenza cases. Because of its high transmissibility and early diagnosis, it isn't easy to manage COVID-19. The popularly used RT-PCR method for COVID-19 disease diagnosis may provide false negatives. COVID-19 can be detected non-invasively using medical imaging procedures such as chest CT and chest x-ray. Deep learning is the most effective machine learning approach for examining a considerable quantity of chest computed tomography (CT) pictures that can significantly affect Covid-19 screening. Convolutional neural network (CNN) is one of the most popular deep learning techniques right now, and its gaining traction due to its potential to transform several spheres of human life. This research aims to develop conceptual transfer learning enhanced CNN framework models for detecting COVID-19 with CT scan images. Though with minimal datasets, these techniques were demonstrated to be effective in detecting the presence of COVID-19. This proposed research looks into several deep transfer learning-based CNN approaches for detecting the presence of COVID-19 in chest CT images.VGG16, VGG19, Densenet121, InceptionV3, Xception, and Resnet50 are the foundation models used in this work. Each model's performance was evaluated using a confusion matrix and various performance measures such as accuracy, recall, precision, f1-score, loss, and ROC. The VGG16 model performed much better than the other models in this study (98.00 % accuracy). Promising outcomes from experiments have revealed the merits of the proposed model for detecting and monitoring COVID-19 patients. This could help practitioners and academics create a tool to help minimal health professionals decide on the best course of therapy.

Performance evaluation of using evacuated tubes solar collector, perforated fins, and pebbles in a solar still - experimental study and CO2 mitigation analysis.

The combination of various methods of increasing evaporation rate can highly impact the performance of solar desalination. This investigation aims to find the impact of using evacuated tubes solar collector, perforated fins, and pebbles on the performance enhancement of a solar still. Simultaneously six-evacuated-tube solar collector to raise the evaporation rate of the system, the perforated fins to increase the heat transfer surface between water and absorber, and the immersed pebbles stone in the water to keep the high water temperature at low solar radiation were considered. The hourly and cumulative distillate output (DO) values are presented separately for the daytime and nighttime to provide extensive insight. The results indicate that on a sample day from the six months of experiments, which was in February 2019, the time for DO peak shifts from 1 to 3 p.m. Moreover, the temperature values for MSS experience almost 43 ℃ jumps on the peak and almost 19 ℃ increase on average compared to CSS. Furthermore, the cumulative DO in the daytime reaches from 2.515 to 6.662 L, while during the nighttime, an increase from 0.057 to 0.872 L is observed. Additionally, during the six months, the average DO jumps from 2.88 to 7.03 L, which means a significant enhancement of 144.1%. Moreover, the costs per liter of MSS and CSS are 0.0051 and 0.0056 dollars per liter, respectively. The net amount of CO2 reduction of MSS was improved by about 2.44 times higher than CSS.

Performance evaluation and financial viability analysis of grid associated 10 MWP solar photovoltaic power plant at UP India.

The main aim of this simulation work is to assess the financial possibility analysis of 10 MWP grid-associated solar photovoltaic (PV) power plants in seven cities i.e. Lucknow, Agra, Meerut, Gorakhpur, Kanpur, Allahabad, and Varanasi of Uttar Pradesh (UP) state of India with the RETScreen Software. The presented research work demonstrates the method of selection of profitable locations for solar PV power plants according to financial viability indicators. It is found that Allahabad city is the most profitable site with values of 16,686 MWh of electricity exported to the grid (EEG), US$20,896.30/year of electricity export revenue (EER), 9.4 years of simple payback period (SPP), 7.7 years of equity payback period (EPP), 19545.9 tCO2/year of GHG emission reduction, US$3492.82/year of the annual life cycle savings (ALCS), 1.5 benefit-cost (B-C) ratio, US$27394.59 of net present value (NPV), 16.5% internal rate of return on equity (IRR-equity), 12.3% modified internal rate of return on equity (MIRR-equity), 5.4% internal rate of return on assets (IRR-assets), and 7% modified internal rate of return on assets (MIRR-assets). The second most profitable site is found in Gorakhpur city and Varanasi city is found the least profitable site. The other two cities, Agra and Kanpur are not found suitable because of the negative values of NPV and ALCS.

A comprehensive review of various approaches for treatment of tertiary wastewater with emerging contaminants: what do we know?

In the last few decades, environmental contaminants (ECs) have been introduced into the environment at an alarming rate. There is a risk to human health and aquatic ecosystems from trace levels of emerging contaminants, including hospital wastewater (HPWW), cosmetics, personal care products, endocrine system disruptors, and their transformation products. Despite the fact that these pollutants have been introduced or detected relatively recently, information about their characteristics, actions, and impacts is limited, as are the technologies to eliminate them efficiently. A wastewater recycling system is capable of providing irrigation water for crops and municipal sewage treatment, so removing ECs before wastewater reuse is essential. Water treatment processes containing advanced ions of biotic origin and ECs of biotic origin are highly recommended for contaminants. This study introduces the fundamentals of the treatment of tertiary wastewater, including membranes, filtration, UV (ultraviolet) irradiation, ozonation, chlorination, advanced oxidation processes, activated carbon (AC), and algae. Next, a detailed description of recent developments and innovations in each component of the emerging contaminant removal process is provided.

Experimental investigation on dish solar distiller with modified absorber and phase change material under various operating conditions.

The shortage of potable water is a global problem. One of the techniques used to participate solving this problem is the solar distiller. The main demerit of solar distiller is its low output yield. So, this work aims at improving the freshwater productivity of a dish solar distiller by enlarging its absorber surface area and increasing its evaporation rate. As a result, the effect of using three different shapes of absorber liner was investigated: convex dish absorber, stepped absorber, and corrugated surface over the stepped absorber. In addition, the absorber of dish distiller was covered by a cotton wick to enlarge the wetted surface area. Also, different water depths (1.0, 2.0, 3.0, 4.0, and 5.0 cm) in dish distiller with stepped absorber were investigated. Moreover, the distance below basin liner was occupied by energy storing medium (paraffin wax + titanium oxide nanoparticles). The performances of dish distiller, dish distiller with stepped absorber, and dish distiller with corrugated absorber were evaluated and compared to that of a conventional solar distiller. Experimental results revealed that the performance of dish distiller with corrugated absorber, wick, and energy storing material was higher than that of dish distiller with stepped absorber, which was better than that of dish distiller, which was higher than that of conventional distiller. As well, the highest improvement in productivity of dish distiller with stepped absorber was 125% compared to conventional distiller and took place at 2-cm water depth. In addition, the productivity of dish distiller with corrugated absorber and wick was improved by 160% compared to that of conventional distiller. Additionally, the highest performance was obtained for dish distiller with corrugated absorber, wick, and energy storing material, where the productivity was augmented by about 183%, and the thermal efficiency reached 69.5%.

In Vitro Degradability, Microstructural Evaluation, and Biocompatibility of Zn-Ti-Cu-Ca-P Alloy.

According to the modern era, zinc is one of the best replacements for human bio-implants due to its acceptable degradation, nominal degradable rate, and biocompatibility. However, alloying zinc with other nutrient metals is mandatory to improve the mechanical properties. In this research, Zn-4Ti-4Cu was alloyed with calcium and phosphorous through a powder metallurgical process to make guided bone regeneration (GBR). First, the sintering temperature of the alloy was found with the usage of thermogravimetric analysis (TGA). Tensile and compression tests showed the suitability of the alloy in strength. The microstructural characteristics were provided with EDS and SEM. The different phases of the alloy were detected with X-ray diffraction (XRD). We can clearly depict the precipitates formed and the strengthening mechanism due to titanium addition. An electrochemical corrosion (ECM) test was carried out with simulated body fluid (Hank's solution) as the electrolyte. Cytotoxicity, biocompatibility, mechanical properties, and corrosion resistance properties were studied and discussed.

Comparative study of double-slope solar still, hemispherical solar still, and tubular solar still using Al2O3/water film cooling: a numerical study and CO2 mitigation analysis.

Solar still, as one of the important devices for generating water using renewable energy, has been widely used in arid as well as coastal areas where access to fresh water is limited. This paper uses CFD simulation to compare double-slope solar still, hemispherical solar still, and tubular solar still using nanofluid film cooling. Al2O3-water nanofluids with a concentration of 0.1% are used due to facilitate sunlight penetration into the absorber plate inside the solar desalination. It is assumed the flow is steady, laminar, and air is an ideal and incompressible gas. The simple algorithm is considered to calculate the relationship between pressure and velocity and to separate the transfer and pressure interpolation terms from the appropriate upstream designs. Also, the economic, exergoeconomic, and CO2 mitigation parameters of various solar stills were investigated. The study revealed that the water productivity of double-slope solar desalination using nanofluids film cooling is improved by about 4.8% compared with tubular solar desalination with nanofluid film cooling. Also, the lowest CPL of 0.0362 $/L was obtained in the double-slope solar desalination using nanofluid film cooling. The net CO2 mitigation of 14.08 tons, 13.72 tons, and 13.44 tons was obtained for double-slope solar desalination, hemispherical solar desalination, and tubular solar desalination, respectively.

Investigating the performance of dish solar distiller with phase change material mixed with Al2O3 nanoparticles under different water depths.

The problem of potable water shortage all over the world made the scientists seek for solutions to overcome this problem. Solar distiller is one of the introduced solutions, but it demerited by the low freshwater output. In this proposed paper, a design modification includes the use of a convex dish absorber instead of the flat absorber liner. The modified solar distiller is nominated by dish solar distiller. The base of dish solar distiller was circular. In addition, a cotton wick was used as a wetting material for facilitating the evaporation process inside the distiller. Besides, the effect of different water heights in the clearance around the dish dome was investigated for 1, 3, 5, 7, 9, and 12 cm. Finally, the space under the dish absorber is filled with a phase change material of paraffin wax mixed with aluminum oxide nanoparticles. Experimental results revealed that the best dish height that provided the highest freshwater productivity was 9 cm, where the average daily yields of dish solar distiller (at 9 cm) and conventional distillers were reported as 4500 and 3000 mL/m2.day, respectively. Then, the productivity of dish solar distiller was improved by around 50% over that of the conventional distiller. In addition, when using the phase change material, the average daily distillate of dish solar distiller was improved by approximately 95% compared to that of the conventional solar still, where the distillate of conventional still and dish solar distiller with phase change material at 9 cm water depth was 3580 and 6980 mL/m2.day, respectively. Besides, the maximum thermal efficiency of dish solar distiller was obtained when using phase change material at 9 cm water depth, where it was 62.4% compared to 30% for the conventional distiller.

Microcontroller PIC 16F877A standard based on solar cooker using PV-evacuated tubes with an extension of heat integrated energy system.

The unavailability of sunlight during nighttime and cloudy weather condition has limited the usage of solar cookers throughout the day. This study will attempt to engineer a solar cooker with PV (photovoltaic panel), evacuated tubes with CPC reflectors, battery, and charge controller using the microcontroller PIC 16F877A. A mathematical model is developed to predict the electrical power (Ep) required during cloudy weather condition and nighttime as well as the temperatures occurring at different parts of the cooker. The proposed model is validated against experimental observations gathered for one of the typical working days of the system. The cooker is tested for various cooking loads to find the cooking time, and it is proven that the proposed cooker can be utilized over 24/7 without interruption.

Artificial Intelligence for Forecasting the Prevalence of COVID-19 Pandemic: An Overview.

Since the discovery of COVID-19 at the end of 2019, a significant surge in forecasting publications has been recorded. Both statistical and artificial intelligence (AI) approaches have been reported; however, the AI approaches showed a better accuracy compared with the statistical approaches. This study presents a review on the applications of different AI approaches used in forecasting the spread of this pandemic. The fundamentals of the commonly used AI approaches in this context are briefly explained. Evaluation of the forecasting accuracy using different statistical measures is introduced. This review may assist researchers, experts and policy makers involved in managing the COVID-19 pandemic to develop more accurate forecasting models and enhanced strategies to control the spread of this pandemic. Additionally, this review study is highly significant as it provides more important information of AI applications in forecasting the prevalence of this pandemic.

Augmenting the productivity of stepped distiller by corrugated and curved liners, CuO/paraffin wax, wick, and vapor suctioning.

This paper aimed to improve the thermal performance of the stepped solar still. So, the effects of using different types of basin liners (corrugated and curved basin liners), jute cloth wick, CuO/paraffin wax, and vapor suction on the stepped solar still performance were investigated. The CuO/paraffin wax was placed into a groove parallel to the basin steps' liner. Also, the stepped distiller was integrated with an external condensation unit. The experimental results revealed that using the corrugated and curved liners increased the productivity of the modified stepped solar still (MSSS) by 42% and 33%, respectively. In addition, using the corrugated liner with wick, corrugated liner with wick and CuO/paraffin wax, corrugated liner with wick, CuO/paraffin wax, and vapor suction improved the freshwater productivity of the distiller by 95%, 127%, and 170%, respectively. At the last studied case (MSSS with corrugated liner, wick, CuO/paraffin wax, and vapor suction), the daily freshwater productivities of the MSSS and conventional still (CSS) were 7000 and 2600 mL/m2·day, respectively. Also, the thermal efficiency of MSSS was calculated as 59% which was obtained at the last studied case. And the efficiency of the CSS was 35%. Besides, the distilled water cost of CSS and MSSS with corrugated liner with wick, CuO/paraffin wax, and vapor suction was 0.023 and 0.014 $/L, respectively.

Current research aspects in mono and hybrid nanofluid based heat pipe technologies.

Technological development has leads to need of more compact thermal management system especially in electronic cooling systems. Heat pipe with the use of mono and hybrid nanofluids are recent trends to satisfy the need of enhanced heat transfer and miniaturization in size. In this article, a state-of-the-art review on different types of heat pipe s, nanofluids preparation and characterization techniques have been carried out. The study begins with an overview of heat pipe and discussed about heat pipe with sintered, grooved and mesh wick structures, applications, mono nanofluids and hybrid nanofluids. The research works carried out for last decade are analyzed in terms of types of heat pipe, working medium, nanofluids preparation and characterization techniques. Effect of operating variables like nanoparticle size, shape and concentration, filling ratio, inclination angle and heat load are also presented. In last, the possible future research thrusts are presented.