Interfacial Connections between Organic Perovskite/n+ Silicon/Catalyst that Allow Integration of Solar Cell and Catalyst for Hydrogen Evolution from Water

The rapidly increasing solar conversion efficiency (PCE) of hybrid organic–inorganic perovskite (HOIP) thin-film semiconductors has triggered interest in their use for direct solar-driven water splitting to produce hydrogen. However, application of these low-cost, electronic-structure-tunable HOIP tandem photoabsorbers has been hindered by the instability of the photovoltaic-catalyst-electrolyte (PV+E) interfaces. Here, photolytic water splitting is demonstrated using an integrated configuration consisting of an HOIP/n⁺silicon single junction photoabsorber and a platinum (Pt) thin film catalyst. An extended electrochemical (EC) lifetime in alkaline media is achieved using titanium nitride on both sides of the Si support to eliminate formation of insulating silicon oxide, and as an effective diffusion barrier to allow high-temperature annealing of the catalyst/TiO₂-protected-n⁺silicon interface necessary to retard electrolytic corrosion. Halide composition is examined in the (FA_1-xCs_x)PbI₃ system with a bandgap suitable for tandem operation. A fill factor of 72.5% is achieved using a Spiro-OMeTAD-hole-transport-layer (HTL)-based HOIP/n⁺Si solar cell, and a high photocurrent density of −15.9 mA cm⁻² (at 0 V vs reversible hydrogen electrode) is attained for the HOIP/n⁺Si/Pt photocathode in 1 m NaOH under simulated 1-sun illumination. While this thin-film design creates stable interfaces, the intrinsic photo- and electro-degradation of the HOIP photoabsorber remains the main obstacle for future HOIP/Si tandem PEC devices.     

Two-sided wind catcher performance evaluation using experimental,numerical and analytical modeling

Experimental wind tunnel and smoke visualization testing as well as CFD and analytical modeling were conducted to investigate the performance of a two-sided wind catcher. This type of wind catcher is divided internally into two halves for the purposes of air supply and extract. In this study, the two-sided wind catcher model was constructed of two similar one-sided wind catcher models, which were attached together back to back. These one-sided models are 1:40 scale models of Kharmani's School wind catcher in the city of Yazd. Experimental investigations were carried out using an open-circuit wind tunnel and both the induced volumetric airflow into the building and the pressure coefficients around all surfaces of the wind catcher model were measured at various wind angles. Furthermore, the CFD simulation was also used to evaluate the pressure coefficient distribution and airflow pattern around and through the wind catcher. Additional experimental tests and computational fluid dynamics simulation of the wind catcher in the wind tunnel were also conducted in order to assess the accuracy of measurement procedures and the uncertainty of experimental results. This article also represents a semi-empirical approach in which experimental data were used for a detailed analytic model, in order to provide an accurate estimate of the performance of wind catchers. It was found that for an isolated two-sided wind catcher model, the maximum efficiency is achieved at the angle of 90°. At this air incident angle the wind catcher efficiency increases approximately 20% more than the one at zero angle. The experimental investigations demonstrated the potential of two-sided wind catcher for enhancing the natural ventilation inside buildings. It can be seen that CFD simulation and analytical modeling results have a good agreement with the experimental results. Theoretical modeling can also help to assess the accuracy of measurement procedures and the uncertainty of experimental results.     

AMBO: All Members-Based Optimizer for Solving Optimization Problems

There are many optimization problems in different branches of science that should be solved using an appropriate methodology. Population-based optimization algorithms are one of the most efficient approaches to solve this type of problems. In this paper, a new optimization algorithm called All Members-Based Optimizer (AMBO) is introduced to solve various optimization problems. The main idea in designing the proposed AMBO algorithm is to use more information from the population members of the algorithm instead of just a few specific members (such as best member and worst member) to update the population matrix. Therefore, in AMBO, any member of the population can play a role in updating the population matrix. The theory of AMBO is described and then mathematically modeled for implementation on optimization problems. The performance of the proposed algorithm is evaluated on a set of twenty-three standard objective functions, which belong to three different categories: unimodal, high-dimensional multimodal, and fixed-dimensional multimodal functions. In order to analyze and compare the optimization results for the mentioned objective functions obtained by AMBO, eight other well-known algorithms have been also implemented. The optimization results demonstrate the ability of AMBO to solve various optimization problems. Also, comparison and analysis of the results show that AMBO is superior and more competitive than the other mentioned algorithms in providing suitable solution.     

Automatic detection of depression symptoms in twitter using multimodal analysis

The Journal of Supercomputing - Depression is the most prevalent mental disorder that can lead to suicide. Due to the tendency of people to share their thoughts on social platforms, social data...     

Synergistic effect of micro- and nano-TiO2 on hydrophobic,mechanical, and electrical properties of hybrid polyurethane composites

Journal of Materials Science: Materials in Electronics - One of the ways to improve the performance of ceramic insulators in polluted climates is to use polymer coatings reinforced with ceramic...     

Effect of Co addition on microstructural and mechanical properties of WC–B4C–SiC composites

In this study, the effect of Co addition on microstructural and mechanical properties of WC-B₄C–SiC composites sintered by spark plasma sintering (SPS) method was investigated. For this purpose, three batches of WC-B₄C–SiC with different contents of Co (10 vol%, 15 vol%, and 20 Vol %) were sintered at 1400 °C. The results of X-ray diffraction (XRD) analysis of the samples indicated the formation of W₂B₅, W₃CoB₃ as well as the remained C phases and unreacted SiC phase. It was observed that by increasing the Co content, the amount of W₂B₅ phase reduces and W₃CoB₃ and C contents increase. Therefore, W₂B₅ peaks were not detected in the sample containing 20vol% Co. Relative density values above 97% were obtained for all the composites. However, a decrease was observed in relative density by increasing the Co content in the composites. The highest flexural strength (510 ± 42 MPa), fracture toughness (10.34 ± 0.82 MPa m^1/2), and hardness (20.63 ± 0.75 GPa) were also obtained for the sample containing 10vol% Co compared to the other samples. In addition, Transgranular fracture of SiC as well as pulling out of W₃CoB₃ and W₂B₅ particles were observed in the fracture surface micrographs of the samples. The presence of micro-cracks in the SiC grains, fracture of W₃CoB₃ grains, and crack deflection was reported as dominant toughening mechanisms.     

Highly efficient electrocatalysts fabricated via electrophoretic deposition for alcohol oxidation,oxygen reduction,hydrogen evolution,and oxygen evolution reactions

Electrophoretic deposition (EPD) is a versatile technique that has drawn attention due to its ease of use and performance in depositing high-quality layers at room temperature. This technique principle is based on the deposition of charged particles from a stable colloidal suspension on a conductive substrate using either a direct or alternating current. Using relatively simple and low-cost equipment, the EPD technique enables the deposition of layers with controlled microstructures at nanoscale. The EPD technique has been particularly successful in the fabrication of the electrocatalyst layers for low-temperature fuel cells, which are anchored on the top of the fuel cell electrodes. In comparison with other electrocatalyst layer deposition techniques such as drop-casting, the EPD technique offers clear advantages for the control of the thickness and packing density of the electrocatalyst layers. Owing to the dense packing density, electrocatalyst layers deposited by EPD could achieve enhanced conductivity and efficiency. The present review aims at comprehensively evaluating the recently published results on the electrocatalyst layers fabricated by EPD and applied in oxygen reduction reactions, alcohol electro-oxidation reactions, hydrogen evolution reactions, and oxygen evolution reactions.     

Production of angiotensin-converting enzyme inhibitory peptides in Iranian ultrafiltered white cheese prepared with Lactobacillus brevis KX572382

In this study, ultrafiltered (UF) Iranian white cheese made with adjunct cultures including six Lactobacillus isolates (Lactobacillus brevis, L. casei and L. plantarum) from traditional Iranian Motal cheese. The peptide extract (<5 kDa) of cheese samples were assessed for angiotensin-converting enzyme (ACE)-inhibitory activity during ripening (5 °C). Among the strains used, L. brevis KX572382 (M8) was selected because of the greater increase in (ACE)-inhibitory activity in the cheese (P < 0.05). The highest activity of M8 extract was observed on the 28th (71.72%) day of ripening (P < 0.05). Proteolytic activity assessment and RP-HPLC peptide profile of M8 water-soluble extracts (WSEs) indicated the effect of M8 on further protein degradation due to secondary proteolysis. A total of 7 different peptide sequences, previously known in the literature for their ACE-inhibitory activity, were tentatively identified by LC/ESI-MS in 28-day M8 peptide extract. Although the effect of M8 on pH and the proteolysis development in cheese was significant, no adverse effect was observed on the sensory properties. In conclusion, M8 strain can enhance the functional properties of Iranian UF white cheese.