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In this work, cobalt phosphate hydrate (Co₃(PO${}_4{)}_2\cdot$8H₂O) was deposited on Ni-foam using the facile hydrothermal method with varied reaction temperatures as 120°C, 150°C and 180°C. The X-ray diffraction analysis reveals the C2/m space group of cobalt phosphate hydrate (CoPH) with a monoclinic crystal structure. Scanning electron microscopy (SEM) evaluates the effect of different reaction temperatures on the morphology of deposited thin film. The change in morphology from microflakes to three-dimensional (3D) microflowers is observed due to temperature variation. In the electrochemical study, the C2 (150°C) electrode delivers a specific capacitance of 8798mF/cm² (specific capacity 1.466mAh cm^–2) at 30mA cm${}^{-2}$ current density. Here, 70.65% of coulombic efficiency was observed over 1500 cycles. The energy density of 0.439Wh/cm² and power density of 9mW/cm² were delivered by optimized CoP electrodes, respectively. EIS study reveals the Rs values of C1, C2 and C3 electrodes are 1.49, 0.97 and 1.3 $\mathrm{\Omega }$, respectively.

The representations of different fingers in the sensorimotor cortex are largely overlapped, which necessitate a good signal-to-noise ratio (SNR) and high spatial resolution to classify individual finger movements from one hand. Electroencephalography (EEG) recorded with disc electrodes has low SNR and poor spatial resolution. The surface Laplacian has been applied to EEG to improve the spatial resolution and selectivity of the surface electrical activity recording. Tri-polar concentric ring electrodes (TCREs) were shown to estimate the Laplacian automatically with better spatial resolution than disc electrodes. For this work, movement-related potentials (MRPs) were recorded from four TCREs and disc electrodes while 13 subjects performed real and imaginary finger movements. The MRP signals recorded with the TCREs have significantly less mutual information and coherence between neighboring locations compared to disc electrodes. The results also show that signals from TCREs generated higher accuracy compared to disc electrodes. It further shows that TCREs using temporal EEG data as features yield an average accuracy of $70.0\pm 7.7$% and $63.3\pm 5.8$% for real and imaginary finger movements, respectively, which is significantly higher than utilizing EEG spectral power changes in $\alpha$ and $\beta$ bands as features. Similarly, with the disc electrodes, it achieved highest accuracy of $46.13\pm 6.77$% and $34.03\pm 5.03$% for real and imaginary finger movements, respectively, with temporal EEG data feature.

Perovskite solar cells (PSCs) without hole transport layer (HTL) based on organic and inorganic metal halide perovskite have received vast consideration in recent years. For predigestion of device structure and construction process, the exclusion of the HTL is a marvelous way. By detaching the HTL part of the devices, we could reduce the cost and complexity of the structures. Currently, a novel 2D material named Ti₃C₂ MXene with high electron mobility, excellent metallic conductivity and functionalized surface groups applied for tuning the energy offsets has been reported to be added in the perovskite absorber layer, leading to a remarkable power conversion efficiency (PCE) improvement. In this work, the role of MXenes in controlling the work function of the involved layers to modify the band alignment towards better performance of the cells is explained. Two HTL free structures of FTO/mTiO₂/cTiO₂/MAPbI₃/Spiro-OMeTAD/Au named as HFRC, and FTO/mTiO₂+MXene/cTiO₂+MXene/MXene/MAPbI₃+MXene/Spiro-OMeTAD/Au named as HFMC were simulated by SCAPS-1D software to study the response of the photovoltaic devices and obtain the highest possible efficiency considering the physics behind. To the best of our knowledge, this is the first time such structures and the results of the current simulation are studied that may be used as a guideline for other practical purposes. We present a modeling procedure that optimizes the thickness of the involved layers and specifies the optimum level of the doping concentration. We also show that by optimizing the work function of the back contact, the device performance witnesses a significant improvement, proving the considerable role of the back contact in these cells. The simulated HTL-free devices illustrate attainably PCEs of about 20.32% and 21.04% for the cells without and with MXene, under AM 1.5G illumination and absorption up to 760 (nm).

High dielectric hafnium oxide films were grown by magnetron sputtering and post heat treatment in nitrogen atmosphere at 500°C for 30 min using vacuum annealing furnace. The film keeps amorphous at 500°C and has better interface quality as revealed by X-ray diffraction and transmission electron microscopy. The influence of TiN and Pt electrodes on the electrical property of the film was compared. For the annealed films, TiN electrode was presented as the optimal one. For the conduction mechanism of Pt/HfO₂/p-Si MOS capacitors under gate electron injection, the dominant conduction mechanism at low electric field is Schottky emission. At high electric field, the conversion of current transport mechanism from Schottky emission to trap-assisted tunneling for the annealed HfO₂ film occurs at 0.64 MV/cm.

Electro-discharge machining (EDM) process is one of the most successful non-conventional machining processes for the last three to four decades in machining very hard materials which are tough to machine by conventional machining process. In the EDM process, besides the erosion of workpiece material, the inherent nature of the process leads to some tool material removal also. This nature of EDM process has been exploited by the researchers which led to the invention of Electro-discharge coating (EDC). EDC is a surface modification technique where tool material gets deposited on the substrate surface due to the sparking effect. It works on reverse polarity to that of EDM. A literature review based on the phenomenon of surface improvement by EDC process and also the future drifts of its application are shown in this paper.

The article is about Ambu and its business in Malaysia.

Judiciously designed phthalocyanines (Pcs), such as silicon-Pc bis(3,5-diphenyl)benzoate (1c), with axial substituents which prevent aggregation, can self-assemble to form ordered nanoporous films on electrode surfaces. In this paper, complementary techniques such as Scanning Kelvin Nanoprobe (SKN) microscopy, Atom Force Microscopy (AFM) and electrochemical measurements are used to demonstrate that films formed by silicon-Pc bis(3,5-diphenyl)benzoate allow size- and charge- selective transport of probe molecules through well-defined intermolecular cavities. In contrast, the analogs silicon-Pc bis(4-tert-butylbenzoate) (1a) and silicon-Pc bis(3-thienyl)acetate (1b) have different film morphologies when solvent-cast in the same manner and block the electrode surface. The role of the different axial substituents in orienting the molecules on the substrate is discussed.

In the past ten years, extracorporeal shock waves have been successfully used in orthopedics. The idea of shock wave therapy is the stimulation of a healing process. Electrohydraulic shock wave therapy provides higher energy density flux than electromagnetic and piezoelectric types. But electrohydraulic shock wave generators are less stable than the other two types because of electrode erosion. In this study, a shock wave generator with a controllable spark gap system has been designed in order to give steady output pressures by automatic adjustment of the electrode gap. An ellipsoidal shock wave reflector is equipped with two AC servo motors with drivers. The motor driver actuates the associated motor which is connected to an electrode base by a belt. On a designed image feedback system, a CCD camera is used as the image detection tool to measure the electrode gap. Experimental results show the coincidence of the second focus of the shock wave reflector with the gas-dynamic focus. Moreover, measurements of focused pressure and energy intensity with PCB and PVDF pressure sensors and tests of stone fragmentation efficiency have been carried out to evaluate the performance of the newly designed shock wave generator with a gap-adjusted system and an image feedback system. It is found that the designed electrohydraulic shock wave generator is stable and efficient in pressure output with a low cost of electrodes.

In our previous study, with the dissipation of quartz crystal through material viscosity is being considered in vibrations of piezoelectric plates, we have the opportunity to obtain electrical parameters from vibration solutions of a crystal plate representing an ideal resonator, in which both full and partial electrodes are considered. In fact, the electrodes of resonators are not symmetrically arranged due to the mounting points of crystal blanks are only in one side. As a result, the study of asymmetric electrodes is necessary for practical applications. Different from previous ones, the vibration solutions will contain both symmetric and anti-symmetric thickness-shear vibrations in the electroded area, which will introduce new boundary conditions. We start with the first-order Mindlin plate equations of a piezoelectric plate for the thickness-shear vibration analysis of a resonator with asymmetric electrodes. The electrical parameters are derived with emphasis on the resistance that is related to the imaginary part of complex elastic constants, or the viscosity. With this approach we can further analyze the actual resonator vibration influenced by the electrode position.