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Cations with suitable sizes to occupy an interstitial site of perovskite crystals have been widely used to inhibit ion migration and promote the performance and stability of perovskite optoelectronics. However, such interstitial doping inevitably leads to lattice microstrain that impairs the long-range ordering and stability of the crystals, causing a sacrificial trade-off. Here, we unravel the evident influence of the valence states of the interstitial cations on their efficacy to suppress the ion migration. Incorporation of a trivalent neodymium cation (Nd3+) effectively mitigates the ion migration in the perovskite lattice with a reduced dosage (0.08%) compared to a widely used monovalent cation dopant (Na+, 0.45%). The photovoltaic performances and operational stability of the prototypical perovskite solar cells are enhanced with a trace amount of Nd3+ doping while minimizing the sacrificial trade-off.

The main outdoor factors that reduce the efficiency of the photovoltaic (PV) panel are the reflection and refraction of light, dirt, dust, and organic waste accumulating on the panel surface. In this article, an antireflection, self-cleaning coating was applied on the PV panel cover glass with a new method. With the coating, the surface has been given a hydrophobic feature. As a coating method, a 3-D printer has not been seen in the literature and used as a new method. The electrospinning method has also been tried as an alternative method. Solutions in different combinations were developed using polylactic acid or polymethylmethacrylate polymer, chloroform ($\text{CHCl}_3$) as a solvent, and silicon dioxide ($\text{SiO}_2$) and titanium dioxide ($\text{TiO}_2$) nanoparticles as primary materials in a modified 3-D printer for bioprinting. Five PV panels were obtained by applying different 3-D parameters from three solutions, which have the best results. Coating thicknesses are in the range of 3.12-8.47 mu m. Coated and uncoated PV panels were tested in outdoor conditions for ten-day periods. The power outputs of the PV panels were measured, and their ten-day average efficiency was presented. According to the results, the highest efficiency increase is 8.7%. The highest light transmittance is 88.2% at 550 nm. In addition, hydrophobic properties were observed on all surfaces and the water contact angle was measured as 96.18 degrees.

Less energy consumption and more efficient use of renewables are among the sustainable energy targets of modern societies. The essential activities to be achieved under these objectives are to increase distributed generation (DG) structures’ applicability. DG systems are small-scale versions of the traditional power grid; they are supported by micro turbines, photovoltaics (PV) modules, hydrogen fuel cells, wind turbines, combined heat and power systems, and energy storage units. The aim of this research is to detail the performance analysis of a proton-exchange membrane fuel cell (PEMFC)-based grid-connected distributed generation system with the help of empirical calculations. To this end, we aimed to establish the system and analyze the performance of the reliable operation of the system with experimental verifications. The findings demonstrate how much power can be generated annually, through real meteorological data, to dispatch to constantly variable loads. While 53.56% of the total energy demand is met by the utility grid, 46.44% of the demand is met by the produced energy i.e., from the DG. The PEMFC-based DG system analyzed in detail in this study was located at Marmara University. According to the results of the performance analysis, significant points of this study will be highlighted to assist the researchers working in this field. Our results are encouraging and can be certified by a larger sample size with neat weather conditions in terms of the percentage of procurement of energy.

This work aimed to comprehensively assess the influence of various surface modifications on the formation of apatite ability for EBM Ti-6Al-4V alloy. Sandblasting (S), acid-etching (E), sandblasting and acid-etching (SE), anodization (NA), micro-arc oxidations in 1M H2SO4solution (SM) and 1M H3PO4solution (PM) methods were applied to modify electron beam melted (EBM) Ti-6Al-4V surface. The α/α’-Ti structures and TiO2phases were detected by XRD. The surface roughness (Ra) values ranged from 0.25 μm and 2.86 μm. The wettability of samples was between around 25° and 104°. The SM sample possessed the lowest contact angle. In vitro tests were employed in the simulated body fluid (SBF) solution for 28 days. The samples with different surface textures demonstrated bioactive behaviors. In vitro test results showed that apatite layers formed on the surfaces. The SM sample exhibited good apatite formation ability when the Ca/P ratios were considered. The apatite formation for the SM sample might derive from high roughness, low contact angle value, the existence of Ti-OH groups, and anatase and rutile phases. The SM can be implemented to boost bioactivity on EBM Ti-6Al-4V alloys.

In this study, sodium caseinate/starch/ tri-calcium phosphate (TCP) base scaffolds were fabricated and cross -linked with microbial transglutaminase. A Maillard reaction was carried out to stabilize the blend of sodium caseinate (8% w/w) and starch (8% w/w) solutions. The dynamics of enzymatic cross-linking activity were assessed with different TCP concentrations. Freeze-dry method was used to extract water from the gel system to acquire a porous, spongy structure. Apart from many other enzymes, microbial transglutaminase has the capa-bility to be active even below freezing temperatures. Keeping at-50 degrees C for 12 h, enzymes were still active to complete the post-crosslinking process. 0.5% TCP case resulted in 690 kPa ultimate tensile strength at dried state. Cell activity and characterization tests were elucidated and observed that those scaffolds can have very prom-ising applications in bone tissue engineering.

This paper proposes a framework to extract knowledge-management elements from business systems in healthcare organizations. According to results of in-depth interviews with experts in the field, a framework is defined, and software was developed to generate log files. Following the application of the Bag of Words (BoW) method on log files of 455 days for feature extraction, the k-means algorithm was used to cluster the feature vectors. The framework was tested with queries for confirmation. The developed framework successfully clustered the generated reports at operational, tactical, and strategic levels to extract knowledge-management elements. This study provides evidence for the knowledge-management pyramid by finding that the generated reports are reviewed mostly at the operational level, then tactical, and then the least at the strategic level. Our framework has the potential to be used not only in the health sector, but also in banking, insurance, and other businesses using business intelligence, especially in accordance with the organization’s goals at operational, tactical, and strategic levels of the knowledge-management pyramid.