Applied Research最新文献

The integrated photovoltaic-thermoelectric cooling systems (PV-TECS) can be used to enhance the performance and life expectancy of commercial PV power plants for sustainable power generation. The objective of the study is to assess the efficacy of PV-TECS to address these concerns. In this study, computational fluid dynamics/finite element method analysis and experimental investigation of photovoltaic micro-modules (PVMM-2) with a thermoelectric cooling system and a reference system without it (PVMM-1), is carried out under real outdoor conditions. The logged data and infrared thermal imaging analysis results show that thermoelectric cooling is very effective in maintaining a consistent PV back temperature difference of 18.24°C between PVMM-2 and the reference system, even reaching subzero temperature when the reference module operates close to 60°C. The simulated results are found to be in close agreement with the experimental results (R² values of 0.83 and 0.94) which allows accurate prediction of system performance under actual solar loading conditions. Further analysis shows that PV-TECS can be effectively used in photovoltaic power plants for efficiency enhancement with a gain in the range of 1%–22% for a monocrystalline PV module depending on location and type of integration. The study is of interest for further research to develop industrial applications.

African horned melon (AHM) (Cucumis metuliferus), indigenous to Kenya. It contains high polyphenol and antioxidant content, yet remains underutilized in food products. This study sought to increase the utilization of AHM by developing a supplemented milk product and evaluating the effects of sundried AHM powder on the physicochemical and sensory properties of the fermented milk product. The fermented milk was supplemented with three different forms of AHM powder: whole fruit, peel, and seed, at concentrations of 0.5%, 0.7%, and 1% w/v. Physicochemical parameters such as pH, total titratable acidity (TTA), syneresis, texture, and viscosity were measured, alongside sensory acceptability assessments. Statistical analysis demonstrated significant differences (p < 0.05) in physicochemical and sensory properties between the control (did not contain AHM) and supplemented samples, particularly at higher concentrations and extended storage periods. The inclusion of AHM powder markedly influenced the fermented milk's properties, with increased TTA and syneresis in samples with higher melon powder concentrations. TTA ranged between 0.32% and 0.46% among all samples during storage which were comparatively higher than the recommended values for fermented milk products at 0.3%. pH findings range was 4.22 and 4.58. The pH range between 4.2 and 4.6 is recommended by FDA for fermented milk. Syneresis were between 2% and 13%. Texture was between 1.24 and 3.95 N. Viscosity was between 1.67 and 3.87 cP. Sensory scores ranged from 8.00 to 2.67 during storage. Fruit seed powder (FSP1) recorded the lowest amount of pH. Control maintained a higher score in the sensory attributes.

Applied Research is a multidisciplinary journal that focuses on bridging fundamental research and practical applications, supporting sustainable problem-solving and global initiatives. The journal covers high-quality research in fields such as Materials, Applied Physics, Chemistry, Applied Biology, Food Science, Engineering, Biomedical Sciences, and Social Sciences. Authors can submit various article types, including Reviews, Tutorials, and Research Articles. The journal aims to highlight innovative research that demonstrates the application of knowledge, methods, instrumentation, and technology into solutions.

Fused filament fabrication (FFF) is the most predominant additive manufacturing technology, not only in the industry but also for many hobbyists. This technology's popularity is because it is inexpensive, user-friendly, and open source. However, compared to other manufacturing processes, like injection molding, FFF products still have some limitations, particularly mechanical properties. Despite this, some post-processing techniques have been developed to improve such properties. One of these techniques involves applying heat treatments (HT). The objective of these HTs is to densify these FFF products and increase the crystallization degree of the semi-crystalline polylactic acid (PLA). This kind of post-processing is claimed to be a viable way to improve mechanical properties. The reprocessing in a powder bed is a type of HT which prevents thermal distortion by using a powder as a mold for the FFF component. The powder should be low cost and have easy access for any user. In this work, this HT was performed in flexural samples with an organic powder (corn flour) and it has improved maximum flexural strength (MFS) and flexural modulus (FM) by 18% and 14%, respectively. The color of parts, before and after HT, was also measured and a slight modification of the response was observed due to the HT. Despite the gains in mechanical properties, it was verified that corn flour produces a considerable amount of smoke during this HT. Thus, it was performed a thermogravimetric analysis (TGA) in three types of powders, namely corn flour, coffee powder, and corn starch. It was concluded that starch is the best one, however considering that all three organic powders release smoke, it is advisable not to use them for HT.

Nigeria is rich in various minerals, including crude oil and solid minerals. However, despite this abundance, effectively utilizing these resources remains a challenge. Kaolin, also known as white China clay, is a crucial raw material used in industries such as ceramics, paper, paint, plastic, and welding electrodes. Despite its plentiful availability in Nigeria, kaolin has not been adequately exploited. Consequently, Nigeria spends approximately 14.35 million USD annually to import refined kaolin to meet local demand, due to the lack of capacity to process it to the required industrial standards. This study investigates the effect of magnesia (MgO) on the morphology and physico-mechanical properties of kaolinitic clay ceramics using the slip-casting method. Various analytical techniques were employed to examine the kaolin, including X-ray fluorescence (XRF), X-ray diffraction (XRD), thermogravimetric analysis (TGA), Fourier Transform Infrared Spectroscopy (FTIR), and Scanning Electron Microscopy (SEM). Also, compressive and flexural tests were conducted. The XRF analysis revealed that all samples contained SiO₂ (54.41%wt), Al₂O₃ (34.05%wt), and other trace elements. The main mineral phases identified were quartz, microcline, and orthoclase. Among the samples, 30–200 exhibited the highest compressive strength at 218 MPa, while the highest flexural rigidity was observed in sample 15–200. The results indicated that MgO significantly affected the properties of kaolin, as the control sample had a compressive strength of 59 MPa. The study also found that the quantities of additives should align with stoichiometric requirements. Results showed hypo-stoichiometry in samples 30–600 and 15–400, and hyper-stoichiometry in sample 60–200. XRF, XRD, and FTIR spectra confirmed the elemental and chemical compositions of the samples, while SEM analysis revealed the morphological structure. It was observed that increasing the magnesia content from 10% to 30% led to an increase in pore spaces within the samples. TGA analysis provided insights into the relationship between mass loss and temperature variation in the ceramic samples, While The DTG curves explain the endothermic phase changes over changes in temperature; at 50–150°C, loss of the water phase is complete, at 300–400°C burning of organic matter phase is achieved and at 500–700°C endothermic dihyroxylation phase begins forming armorphous meta-kaolin.

This tutorial-style article describes recent improvements in the quantitative application of energy-dispersive X-ray spectroscopy and mapping in electron microscopes to semiconductors, with a focus on spatial resolution, sensitivity and accuracy obtainable in characterising the chemical composition of thin layers, quantum wells and quantum dots. Various approaches applicable in scanning electron microscopy of bulk and (scanning) transmission electron microscopy of thin film samples are outlined. Applications to semiconductor quantum well systems, mainly based on indium gallium arsenide and silicon germanium studied in the author's laboratory, are provided as examples.

Lithium-sulfur battery (LSB) chemistry is regarded as one of the most promising contenders for powering next-generation electronics, including electric vehicles. This is due to its high theoretical capacity, the use of inexpensive and environmentally friendly materials, and its alignment with climate-smart manufacturing principles. Sulfur, the electroactive element in LSBs, undergoes lithiation to form a series of polysulfides, each contributing to the battery's energy density. However, this chemistry encounters several challenges, particularly concerning the stability of sulfur. Recent studies have shown that the presence of a full gamma phase of sulfur in an LSB cathode significantly enhances the capacity and overall cell performance. However, despite the advantages of cathodes with gamma sulfur, the characteristics of LSBs with mixed crystal phases of sulfur (alpha, beta, and gamma) have not been extensively studied. In this context, we developed a simple and cost-effective synthesis method to produce both single-phase (alpha) and mixed-phase sulfur (primarily a mixture of alpha and gamma, with a trace of beta) and conducted their detailed physical and electrochemical characterization for use as electroactive cathode materials in LSBs. The cells fabricated using sulfur-carbon black as the cathode delivered a specific capacity of approximately 640 mAh/g at a current density of 275 mA/g, demonstrating excellent cyclic stability over 50 cycles with a capacity retention of around 97%. This performance is superior to that of the sulfur-baked carbon black composite cathode, which achieved 440 mAh/g at the same current density.

The lungs are exposed to a hostile environment from both sites: the airways and the vasculature. However, an efficient gas exchange of oxygen (O₂) and CO₂ is only possible through a very thin alveolo-capillary membrane. Therefore, maintaining cell barrier integrity is essential for respiratory health and function. On the vascular site, endothelial cells form a natural barrier, while in the airways epithelial cells are most important for protection of the lung tissues. Moreover, fibroblasts, by transforming to myofibroblasts, are essential for wound closure after mechanical and chemical microinjuries in the respiratory tract. Along this line, loss of cell resistance in vascular endothelial and lung epithelial cells enhances invasion of pathogens (e.g., SARS-CoV-2) and results in pulmonary edema formation, while increasing barrier function of pulmonary (myo)fibroblasts blocks gas exchange in patients with pulmonary fibrosis. Therefore, electrical cell-substrate impedance sensing-based quantification of changes in cell barrier function in lung endothelial and epithelial cells as well as fibroblasts after application of harmful triggers (e.g., hypoxia, receptor agonists, and toxicants) is a convenient and state-of-the-art technique. After isolation of primary cells from mouse models and human tissues, changes in cell resistance can be detected in real time. By using lung cells from gene-deficient mouse models, microRNAs or the small-interfering RNA technology essential proteins for cell adhesion, for example, ion channels of the transient receptor potential family are identified in comparison to wild-type control cells. In the future, these proteins may be useful as drug targets for novel therapeutic options in patients with lung edema or pulmonary fibrosis.

A novel approach exploiting surfaces and interfaces between liquid oils and porous soil media was used to investigate the role of xanthan gum (XG) in minimizing the spread of petroleum oil spills on land. 1.6 wt% XG added to soil-based mixture matrixes (topsoil, sand, clay, and moisture) resulted in a 50% reduction in oil spreading area at 0 and 5 wt% moisture content, at 1.3 cm depth of soil matrix. Also recorded was a 45% increase in time taken for the low- and medium-viscosity oils to penetrate this soil depth. XG alters the surface energy and roughness of the soil matrixes, which additionally contributes to a reduction in oil spreading capabilities. Interfacial phenomena between individual oil droplets and soil matrixes demonstrated variable findings of droplet spreading and penetration with XG, depending upon the heterogeneity of the soil matrix itself. XG assisted a reduced lateral spread in heterogeneous soil matrixes and a reduced vertical penetration in clay-based matrixes. These interfacial results highlighted the often-observed differing transport phenomena at the interface compared with the bulk. This initial study demonstrates a novel approach to incorporate surface energy phenomena into the suite of soil remediation efforts by introducing natural biopolymers in high-risk land oil-spill areas to slow oil contaminant spread. Future studies will further characterize the benefits of XG in containing oil flow.