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Fabrication and evaluation of NaSrEr(BO3)2 interlayer in Al/Si photodiode structures for photodetector applications
No full textThis study investigates the synthesis, characterization, and application of Al/NaSrEr(BO3)2/n-Si and Al/NaSrEr(BO3)2/p-Si photodiodes (PDs). The NaSrEr(BO3)2 compounds were synthesized and deposited onto n-type and p-type Si wafers via spin coating, followed by the formation of aluminum electrodes using thermal evaporation. Comprehensive characterization was conducted using FT-IR, powder X-ray diffraction (P-XRD), ICP-MS, thermogravimetric/differential thermal analysis (TGA/DTA), and SEM–EDS to investigate the structural, compositional, and morphological properties of the orthoborate films. FT-IR spectra confirmed the vibrational modes of the borate structure, while P-XRD analysis revealed crystalline phase formation. ICP-MS results verified elemental ratios consistent with theoretical predictions, and SEM–EDS provided insight into surface topography and elemental distribution. The optical and electrical behavior of the fabricated photodiodes was assessed through Current–Voltage (I–V) and Current–Time (I–t) measurements. Device performance metrics such as ideality factor, barrier height, responsivity, and specific detectivity were derived. Under an illumination intensity of 100 mW/cm2, the NaSrEr(BO3)2/n-Si device exhibited a responsivity of 1.28 A/W and a detectivity of 5.91 × 1010 Jones. In contrast, the NaSrEr(BO3)2/p-Si photodiode delivered enhanced performance, with a responsivity of 2.38 A/W and detectivity of 7.82 × 1010 Jones. This research highlights the potential of NaSrEr(BO3)2-based materials for enhancing the performance of photodiodes and sensor systems, while also laying the groundwork for future advancements in borate-based optoelectronic devices
Airfoil Shape Manipulation Using Pressure-Driven Soft Actuators
No full textThis paper presents a comprehensive analysis of the response characteristics of pressure-driven soft actuators and their application in airfoil shape manipulation, focusing on certain regions such as the leading edge, trailing edge, and mid-chord region. Pressure-driven soft actuators, consisting of elastomeric materials for deformation and high-strength materials for structural integrity, exhibit shape-changing capabilities when subjected to internal pressure. finite element models are developed to analyze the structural response of these soft actuators under varying parameters such as pressure levels, cross-sectional layouts, elastomeric material properties and restraining plate configurations. Results indicate that internal pressure levels and material properties affect both axial and bending displacement while restraining plates further enhance bending response for varying cross-sections of soft actuators. The integration of these soft actuators on an airfoil geometry demonstrated potential for optimizing aerodynamic performance for various mission requirements. The result of this research provides insights for designing more adaptive and efficient morphing airfoils using pressure-driven soft actuators
DARKIN: a zero-shot benchmark for phosphosite–dark kinase association using protein language models
No full textMotivation: Protein language models (pLMs) have emerged as powerful tools for capturing the intricate information encoded in protein sequences, facilitating various downstream protein prediction tasks. With numerous pLMs available, there is a critical need for diverse benchmarks to systematically evaluate their performance across biologically relevant tasks. Here, we introduce DARKIN, a zero-shot classification benchmark designed to assign phosphosites to understudied kinases, termed dark kinases. Kinases, which catalyze phosphorylation, are central to cellular signaling pathways. While phosphoproteomics enables the large-scale identification of phosphosites, determining the cognate kinase responsible for the phosphorylation event remains an experimental challenge. Results: In DARKIN, we prepared training, validation, and test folds that respect the zero-shot nature of this classification problem, incorporating stratification based on kinase groups and sequence similarity. We evaluated multiple pLMs using two zero-shot classifiers: a novel, training-free k-NN-based method, and a bilinear classifier. Our findings indicate that ESM, ProtT5-XL, and SaProt exhibit superior performance on this task. DARKIN provides a challenging benchmark for assessing pLM efficacy and fosters deeper exploration of under-characterized (dark) kinases by offering a biologically relevant test bed. Availability and implementation The DARKIN benchmark data and the scripts for generating additional splits are publicly available at: https://github.com/tastanlab/darki
Investigations on the effect of secondary treatments on Ti48Al2Cr2Nb alloy manufactured by electron beam powder bed fusion method
No full textAs-built Ti48Al2Cr2Nb alloy samples produced by electron beam powder bed fusion (PBF-EB) exhibited notable brittleness. The low ductility was attributed to coarse γ bands aligned perpendicular to the building and tensile direction. Additionally, variations in aluminum content and hardness between the coarse colonies and fine γ/α2 lamellae contribute to this phenomenon. Electron backscattered diffraction (EBSD) studies revealed a higher amount of dislocation density and inherent strain after PBF-EB manufacturing. Hence, usage of Ti48Al2Cr2Nb alloy in the as-built condition in aviation applications with high loads and demanding environments is not found to be viable. To eliminate these negative aspects and make PBF-EB produced Ti48Al2Cr2Nb alloy available for demanding applications, two distinct post-processing heat treatments; namely, hot isostatic pressing (HIP) and annealing heat treatment (HT) were employed at 1200 °C. A comprehensive characterization covering microstructure analysis, EBSD, fracture surface examination, as well as room and high-temperature tensile tests allowed determination of the effect of post-processes. HIPing altered the banded structure observed in the as-built samples by increasing the amount of α2 phase and grain size. On the other hand, HT made the banded structure more pronounced without significantly increasing the amount of α2 phase. HT also strengthened the texture, while HIPing introduced randomization of grains. On the other hand, complete recrystallization is achieved as a result of HT at 1200 °C for 2 h, whereas HIPing at the same temperature for 2 h induced only 80.5 % recrystallization. In both post-processes, dislocation density and inherent strain were reduced. Room temperature and high-temperature tensile tests demonstrated that both HIPing and HT eliminated the extreme brittleness of the as-built samples
EXPLORING THE PERCEIVED CHALLENGES IN THE PROVISION OF BIODIVERSITY-RESPONSIVE ENERGY SUPPLY
No full textTrajectory tracking controller design and simulation of a tethered aircraft
No full textThis study addresses the control problem of an airborne wind energy aircraft, generating power on the ground. The proposed control tracks a pre-defined trajectory in the power generation phase. The reference attitude information is computed by the trajectory tracking controller so that the aircraft carries out a coordinated turn and maintains a proper pitch attitude to generate the necessary lift to pull the winch. A novel quaternion-based nonlinear attitude controller is designed, utilizing the attitude commands generated by the tracking controller. A six degrees of freedom mathematical model of the aircraft together with the winch is modeled. Besides the power generation phase, the rewind phase, triggered when the maximum tether length is achieved is taken into account as well. The success of the developed controller is demonstrated through several nonlinear simulation-based flight tests. The generated power is compared with the theoretical maximum value and other sources from the literature
Geotechnical analysis of gravity anchors for floating solar energy systems
No full textFloating solar energy systems (FPV's) are being used on inland water bodies (e.g. ponds, lakes and reservoirs) as well as offshore. FPV systems are connected to seabed / lakebed via mooring lines and anchors which are vital components of the entire system in terms of stability and durability of floating solar installations. Bathymetry, water depth, wind patterns, waves, currents, fluctuations in water level and seabed/lakebed soil properties play a central role in determining the best anchoring solution. This study focuses on the geotechnical design of gravity anchors to explore the failure mechanisms (e.g. sliding, overturning) and provides preliminary sizing of anchors considering anchor efficiency, which is defined as the ultimate holding capacity/buoyant weight of anchor. A square-shaped, gravity anchor made of concrete, with mooring line connection from the top of the anchor (top padeye case), located on clay seabed is studied. The effects of (i) the distance of the mooring line connection point from the edge of the anchor, and the ratio of height to width of anchor, on anchor efficiency, are investigated. The results indicate that, these parameters influence the anchor efficiency, hence the ultimate holding capacity of the anchors
