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Nano carbon film was synthesized on a nickel substrate in molten LiCl-KCl-K₂CO₃ salt by an electrolytic deposition method. The influence of pulse frequency on the property of the carbon films was studied. Over the carbonate ion concentration range of 0.10–0.20 mol%, the mass of carbon film on unit area increases with increasing pulse frequency over the range of 0.05–33Hz or 33–166Hz, whereas, it decreases with increasing pulse frequency over the range of 33-166Hz. It means that a critical pulse frequency exists, which can be thought to correspond to the natural vibration frequency of the film. When the electrolytic pulse frequency is equal to the natural vibration frequency of film, a resonance maybe happen, and the film exfoliates.

In this study, the problems of the low deposition rate and bath instability in chemical deposition can be effectively solved by using the pulsed current-assisted chemical deposition process when preparing Ni–P alloy coating. Orthogonal experiments were designed by changing the average current density, pulse frequency and duty ratio of the pulses to study their effects on the deposition rate and hardness of the coatings. Compact Ni–P coating with uniform surface morphology and good performance was prepared by parameter optimization. The results show that our method can greatly improve the deposition rate while ensuring the surface quality and performance of the deposited layer.

The investigation deals with the turning of Alumina (Al₂${\text{O}}_3)$ ceramic using various parameters of the input process. The experimental design has been used based on Taguchi technology to perform the experimentation. Pulse frequency, average laser power, work piece rotational speed and feed rate are the process inputs considered during investigation. The Signal-to-Noise ratio values are used for measuring various outputs. The best amount of spot overlap has been reached with various combined parameter settings. In addition, a better width of the rotational scan has been attained by varying axial feed rate as well as the rotational speed of the work piece. Micro-turned deviation (depth) and machined surface finish at different input parametric combinations were considered as output reactions for machining. During the laser turning operation, analyses learned the effect of overlaps on the various inputs considered for output measurements such as micro-degree deviation and surface roughness. The investigation reveals that the surface finish decreases with an increase in overlap in the circumferential direction and rotation of the work sample. The maximum surface finish is 0.507$\mu$m achieved at a frequency of 5000Hz, 300rpm work piece cutting speed, 8.5W power and 0.4mm/s feed.

This paper describes the pulsed Nd:YAG laser machining characteristics on 6351 aluminum reinforced with silicon carbide (SiC) and boron carbide (B₄C) particles. The composites are prepared using stir casting route by varying the weight percentage of B₄C (0, 5, and 10 wt.%). During experimentation, the traverse speed (5, 15, and 30 mm/s) and the laser pulse frequency (5, 9, and 15 kHz) are considered to evaluate the groove width. The results reveal that the lower pulse frequency produced poor groove surface quality. Higher thermal energy dissipation at lower traverse speed may also result in the formation of recast layer and heat-affected zone. This is evident from the microscopic image and the EDS analysis. Thus, the optimum condition (composite with 10 wt.% B₄C machined at 30 mm/s and 15 kHz) to achieve minimum grove width with improved surface morphology is identified by desirability analysis. Additionally, the regression model is developed to predict future values ($R$² at 91.86% and $R$² (adj) at 87.55%). Finally, the probability plot confirms the effectiveness of the proposed model at 95% confidence level.

For a new class of neuron models we demonstrate here that typical membrane action potentials and spike-bursts are only transient states but appear to be asymptotically stable; and yet such metastable states are plastic — being able to dynamically change from one action potential to another with different pulse frequencies and from one spike-burst to another with different spike-per-burst numbers. The pulse and spike-burst frequencies change with individual ions' pump currents while their corresponding metastable-plastic states maintain the same transmembrane voltage and current profiles in range. It is also demonstrated that the plasticity requires two one-way ion pumps operating in opposite transmembrane directions to materialize, and if only one ion pump is left to operate, the plastic states will be lost to a rigid asymptotically stable state either as a resting potential, or a limit cycle with a fixed pulse frequency, or a spike-burst with a fixed spike-per-burst number.