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The present study investigates the effect of different volume ratios of PCM on the melting process and energy storage in the improved thermal energy storage (TES) system using auxiliary fluid. The purpose of using the auxiliary fluid is to benefit from the density difference between the auxiliary fluid and the PCM, which improves the convection heat transfer in the auxiliary fluid and increases the melting speed of the PCM. The auxiliary fluid, which has a higher density, is placed on the solid PCM at the beginning of the melting process and takes the place of the melted PCM during the melting process. This displacement causes better heat transfer between auxiliary fluid, PCM, and hot wall. Five different PCM/auxiliary fluid volume ratios are studied, including 30, 40, 50, 60, and 70% of PCM. The rate of energy storage in the system increases to 0.341 kW/kg, the highest rate of energy stored in the system and in PCM, corresponding to a volume ratio of 30% of PCM. Although the total energy stored in the system increases with an increase in the PCM volume ratio, the energy storage rate in the system increases with a decrease in the PCM volume ratio. Therefore, the optimal use of the most appropriate volume ratio of PCM is of great importance.

This study aims to investigate the influence of radiation, thermal conductivity and variable viscosity on natural convective flow on a semi-infinite perpendicular plate. Variable viscosity, thermal conductivity and thermal radiation are considered for the given study. The dimensional governing equations are framed with the use of the mentioned parameters and then these equations were converted into dimensionless equations by applying non dimensional quantities. The main aim of this study is to find the Nusselt number and skin friction for both air and water for considered parameters. Using the finite difference method through Fortran software, numerical solutions to the governing heat equations and dimensionless momentum equations were computed. The results for the parameters thermal conductivity, variable viscosity, radiation, and Prandtl number for both air and water are displayed via various graphs. The skin friction coefficients, Nusselt parameter, and local Nusselt numbers were discussed for both the air and water. The key conclusions of this study are that the succeeding velocity declines as the radiation's increases. By increasing the radiation value and the fluctuation time, the temperature distribution increases. Notably, the temperature profile increases significantly when the variable viscosity parameter decreases.

The performance of polymer:fullerene bulk heterojunction (BHJ) solar cells is significantly influenced by the morphology of electron donor and acceptor blends under the premise that electronic structure is complimentary regarding donor and acceptor materials. There are many cases where intimate mixing of donor and acceptor perturbs the electronic structure, which fundamentally changes the transport and photovoltaic characteristics. Here, we present the bimolecular crystal packing of polymers and fullerenes, and investigate the correlation between device performance and structural details. We find that bimolecular crystallization can reorganize polymer chain packing, leading to poor electron transport and device performance. The size compatibility and the passivation of entropy penalty led to cocrystallization instability, which was clearly seen byin situGIWAXS data. PC61BM is found to intercalate into side chains of PQT by reorganizing both PQT and PC61BM, forming stable, highly ordered bimolecular crystals. The poor electron transport in bimolecular crystal domain could account for the poor device performance in both perovskite and organic solar cells. Bis-PC61BM, on the other hand, only forms loosely packed aggregates in solution, and then rapidly phase separated into large domains with an edge-on interfacial orientation and performed poorly in solar cells.

Wind power provides a clean and feasible solution to generate electricity. The development of wind power applications requires a deep analysis of wind profiles and an accurate prediction of wind energy at a study site. This work explores the distribution of wind speed to estimate the two Weibull parameters (shape and scale) that are widely utilized for modeling and providing an accurate and efficient estimation of wind resource and power. These two parameters are calculated based on measured daily wind speed data from 2008 to 2018, collected in Jerusalem, Palestine. Three assessment criteria were used to assess the goodness of fit; they are Root Mean Square Error (RMSE), Mean Absolute Percentage Error (MAPE), and chi-square. The findings revealed that of the five estimation methods being considered in this study, both the Empirical Method (EM) and the Method of Moment (MoM) were the most accurate in determining the values of the Weibull shape and scale parameters to approximate wind speed distribution at the study site. Based on the goodness-of-fit tests, both methods provide lower values of the used assessment criteria. The statistical performance tests rejected the Energy Pattern Factor Method (EPFM) as an adequate method due to the higher values of chi-square and revealed that the Maximum Likelihood (MLM) and the Modified Maximum Likelihood (MMLM) methods ranked third and fourth, respectively.

ABSTRACT Objective: Neonatal jaundice is characterized by a yellowish coloration of the skin and sclera of newborn infants and elevated serum bilirubin levels. In this study, it was aimed to evaluate the knowledge, practices and attitudes of primigravidas in Diyala province of Iraq regarding neonatal jaundice. Material and Methods: A questionnaire was applied to 165 women who were primigravidas between January 1, 2022 and March 31, 2022 in hospitals and health centers to evaluate their knowledge, practices and attitudes about neonatal jaundice. Results: Although 71.4% of the women knew the two signs of neonatal jaundice, 78.8% of them did not know any of the dangerous signs of neonatal jaundice. 28.4% of women knew that there are two effective treatment methods for the treatment of neonatal jaundice. 57.6% of the women were not aware of any of the severe complications of neonatal jaundice. Conclusion: Most of the primigravida in this study decided to visit physicians when their babies have jaundice without using traditional treatment.

The flow mechanism and entropy production of a bi-convective, magnetized, radiative nano-liquid flow for an inverted cone considering temperature-sensitive water properties is accomplished numerically. The functional nanomaterial comprises Copper, Alumina in the base liquid, water. The mathematical equations representing the system's physical characteristics are solved numerically by adopting a robust numerical approach for indulgencing non-similar solutions to understand numerous parameters' effect on temperature, velocity, salient gradients, and entropy production. The investigation summarizes that buoyancy force and injection heighten the velocity, and suction, particle percentage, radiation elevate the heat transfer. At the same time, the radiation and Brinkman number enhance the entropy generation. It is also detected from this investigation that the magnetic effect shows dual behaviour in entropy generation.

A new theoretical tri-hybrid nanofluid model for enhancing the heat transfer is presented in this article. This model explains the method to obtain a better heat conductor than the hybrid nanofluid. The tri-hybrid nanofluid is formed by suspending three types of nanoparticles with different physical and chemical bonds into a base fluid. In this study, the nanoparticles TiO2, Al2O3 and SiO2 are suspended into water thus forming the combination TiO2-SiO2-Al2O3-H2O. This combination helps in decomposing harmful substances, environmental purification and other appliances that requires cooling. The properties of tri-hybrid nanofluid such as Density, Viscosity, Thermal Conductivity, Electrical Conductivity and Specific Heat capacitance are defined mathematically in this article. The system of equations that governs the flow and temperature of the fluid are converted to ordinary differential equations and are solved using RKF-45 method. The results are discussed through graphs and it is observed that the tri-hybrid nanofluid has a better thermal conductivity than the hybrid nanofluid.