Ammonia (NH3) has been suggested as a fuel to attain zero carbon emissions. However, dealing with ammonia needs careful studies to reveal its limits as a suitable and promising fuel for broad applications within large power requirements. Chemical reaction mechanisms, widely employed in the modeling of these applications, are still under development. Therefore, this review is aimed to shed light on the current mechanisms available in the literature, highlighting modeling parameters that directly affect reaction rates which in turn govern the per-formance of each reaction mechanism. The key findings denote that most of the reaction mechanisms have poor performance when predicting combustion characteristics of ammonia flames such as laminar flame speed, ignition delay time, and nitrogen oxide emissions (NOx). In addition, none of the mechanisms have been opti-mised efficiently to predict properly experimental measurements for all these combustion characteristics. For example, Duynslaegher's mechanism perfectly predicted the laminar flame speed at lean and stoichiometric conditions, while Nakamura's reaction mechanism worked properly at rich conditions for the estimation of laminar flame speed. Although the aforementioned mechanisms achieved good estimation in terms of laminar flame speed, they showed poor performance against NO mole fractions. Similarly, Glarborg's (2018) mechanism properly estimated NO mole fractions at lean and stoichiometric flames while Wang's mechanism performed well in rich conditions for such emissions. Other examples are presented in this manuscript. Finally, the prediction performance of the assessed mechanisms varies based on operating conditions, mixing ratios, and equivalence ratios. Most mechanisms dealing with blended NH3 combinations gave good predictions when the concentration of hydrogen was low, while deteriorating with increasing hydrogen concentrations; a result of the shift in re-actions that require more research.

Great efforts have been paid to enhance the photoelectrochemical performances of LaFeO3. However, there have rarely been reported about modifying of LaFeO3 with transitional metal borides for enhanced photoelectrochemical activities. Herein, we prepared LFO/Ni–B composite electrodes by immersing LFO into the prepared electroless plating solution. The optimized LFO/Ni–B composite exhibits a 373% improvement of the photocurrent density and exhibits an anodic shift of onset potential. Systematic studies reveal that the improvement of PEC activity should be attributed to enhanced electrochemically active surface area and electrocatalytic properties, reduced resistance of the PEC system, and a more pronounced downward band bending at the photoelectrode/electrolyte interface.

Identifying effective means to improve the charge separation performance assisted by adequate surface reaction represents a significant challenge for developing a highly efficient TiO2 photoanode. Here we report a structural synergistic strategy between a close contact heterojunction and a surface oxygen vacancy to significantly boost the charge separation efficiency and charge injection efficiency of TiO2 nanowires (NWs) in PEC water splitting. To accomplish this task, a TiO2/SrTiO3 (TiO2/STO) heterojunction was first constructed by in situ conversion, resulting in close contact between interface, promoting separation of the photoinduced charge carriers, which increased charge separation efficiency by 107% compared to TiO2. After the amorphous layer was established on the surface of the SrTiO3 coating, the resulting TiO2/SrTiO3/r-SrTiO3 (TiO2/STO/r-STO) improved the light absorption property of the photoelectrodes and boosted the ability to adsorb the reactant hydroxide ions, resulting in charge injection efficiency improvement by 67.3% compared with pure TiO2. This complementary modification for enhancing charge separation and boosting the surface reaction demonstrates a significant capacity to improve the photoelectrochemical (PEC) performance of one photoanode, which could be instructive for other fields including photocatalysis and PEC carbon dioxide reduction.

Due to an appropriate band gap of 2.07 eV, perovskite LaFeO3 (LFO) is an alternative candidate for high-efficiency photoelectrochemical (PEC) systems. However, the photocurrent of the LFO photocathode is too low to be practical. Herein, we prepared a LFO film with high crystal quality by inserting an Au thin layer between LFO and FTO in the LFO/FTO photocathode. Accordingly, an effective improvement PEC performance could be obtained and the photocurrent density of the FTO/Au/LFO electrode was increased to -19.60 μA cm-2 at 0.6 V vs. RHE, which is 4.1 times higher than that of pristine FTO/LFO electrode. Based on the experimental and theoretical analysis, the enhancement of the photocurrent was attributed to the strong light harvesting, enhanced charge separation, and increased charge-collection efficiency of the Au/LFO structure. This work provides a promising strategy to develop high-efficiency PEC electrodes, and has potential to be applied in the visible-light water splitting area.

Aiming at the problem of fault location and signal interference in transmission line,a fault location method of transmission line combining VMD (variational modal decomposition) with soft mathematical morphology was put forward in this paper.Firstly,VMD is used to decompose noisy signals,and a part of noise is automatically filtered out in the decomposition process.Then,the residual interference is further removed by the average flexible morphological filter.Finally,the flexible shape edge detection is used to amplify the singular point of the signal,and then,the output threshold is set to reduce the influence of the noise background on the abrupt change of the signal.The experimental results show that the proposed method has good noise robustness,and can suppressthe noise interference and amplify the traveling wave characteristic signal.It can detect the fault line of the transmission line effectively and obtain higher detection accuracy.

Partial discharge(PD)test is an important means to detect the insulation performance of power cable.Be-cause the electromagnetic environment of the test site is complicated,the extracted PD signal is submerged by noise. In order to get a more real PD signal,this paper proposes a de-noising method based on wavelet transform and high or-der partial differential equation(PDE).It adopts wavelet transform to provide better pre-processing and post-process-ing platform of partial discharge signal,and utilizes the fourth-order PDE to iterate the low-frequency sub-signal.At the same time,the signal to noise ratio(SNR)is used as the iteration termination condition.The de-noising effect of this method is compared with the traditional wavelet threshold de-noising effect.Finally,the experimental and simula-tion results show that this method can suppress noise effectively and keep the property of edge and detail.It has better de-noising performance than traditional wavelet threshold de-noising method.

The voltage level of power system is continuously improved. Partial discharge (PD) test is an important means to detect the insulation performance of high voltage electrical equipment. The electromagnetic environment of the test site is complicated. The extracted PD signal is submerged by noise. In order to get a more real PD signal, noise removal is inevitable. Aiming at this aspect, this paper proposes using empirical mode decomposition (EMD) and high order partial differential equation (PDE) to suppress the interference signal. The simulation results show that using this method to deal with the effect of PD signal is very obvious.