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Magnetic field assistance electrochemical micro-machining strategy was used to produce 304 stainless steel with a high-precision surface. The surface roughness was measured and the micro-morphology was observed. The results showed that the optimal surface morphology with a roughness of about 0.30 μm was obtained after magnetic field assistance electrochemical micro-machining for 10 min. The magnetic field assistance electrochemical micro-machining produced a lower surface roughness than that of electrochemical micro-machining at the same processing time, indicating that magnetic field assistance was beneficial to improving the machining efficiency. The surface microstructures proved that the magnetic field assistance electrochemical micro-machining provided a relatively flat and smooth surface. The stray corrosion was significantly reduced. The generation of the electromagnetic force regulated the charge transfer in processing and affected the behavior of the anode dissolution reactions. The physical models describing the mechanism of stray corrosion suppression were established.

The global pursuit of low-carbon technologies has led to the rapid development of renewable energy sources (RES), such as wind and solar power. The large-scale integration of RES into power grid systems can change the characteristics and forms of the system inertia. RES-heavy power systems exhibit lower inertia, compromising their frequency stability and rendering traditional inertia response mechanisms and analysis methods insufficient. This review compares the different inertias in traditional and future RES-heavy power systems, details the inertia response mechanisms of various types of devices, identifies deficiencies in the traditional inertia index when quantifying the inertia response capabilities of the equipment, and illustrates the necessity of exploring a generalized inertia index suitable for such systems. Furthermore, the influence mechanism of system inertia on frequency stability is analyzed, and the action mechanism and response time sequence of various types of devices in the system inertia response are described. The challenges in applying the traditional frequency stability analysis method to future RES-heavy power systems are also identified. This review can serve as a guide for developing power grid control systems and analysis methods to accommodate the increasing application of RES.

The orthogonal experiments of electrochemical machining (ECM) of 2Cr13 stainless steel were conducted. There were many process variables such as working voltage, rotational speed, interelectrode gap, duty cycle, and pulse frequency involved in ECM, and it was difficult to determine an appropriate parameter combination to minimize material removal thickness and surface roughness for electrochemical polishing. For obtaining the optimal processing parameters of ECM, the analyses of variance (ANOVA) and grey relational analysis (GRA) were used to optimize the experimental data. The solutions acquired by the analysis of ANOVA and GRA were compared and experimentally validated. Despite the divergent optimal parameter combinations, the confirmation experiments recorded almost the same removal amount and surface roughness after 15 min of processing time, the high-quality surface of the samples were obtained. As the comparison strategy to evaluate the two data processing methods, the observation results of micro-morphology revealed that the surface of the samples processed with the optimal parameters obtained by GRA had more attractive surface flatness with the Szof 1.5640 μm than that with the Szof 1.8820 μm obtained by ANOVA, which verified the application of GRA in the superiorization methodology. This study provided an idea for the selection of optimal processing parameters obtained by different analysis methods in ECM, and high-quality surfaces were obtained.

Engineering-procurement-construction project type is widely used in the industry of power generation development, and logistics management has been playing an important role. Logistics, in the area of power generation industry, can be a very complicated system as it typically involves many participants who undertake a number of operational activities and subsequently includes a number of interfaces which need to be properly dealt with. To enhance the management and control from an EPC contractor's point of view, a 'one-item-multiple-code' approach is proposed so as to realise the traceability of items and related operations along the logistics phase. The presented approach imitates the relationship of ID no. and other certificate numbers by the use of KKS being unique and fundamental code. Its merits and demerits are analysed in detail. The implementation and developed IT system based on the approach are subsequently discussed. Finally, the paper goes on to point out two directions which need to be further exploited by future research.

Abstract: The pseudobinary Ti0.5Ni0.5-Ti0.5Cu0.5 system was analyzed using thermodynamic models for the Gibbs energy of individual phases in the system. The TiNi intermetallic phase crystallizes with the B2 CsCl-type structure and is an ordered form of the A2 BCC structure. It was treated with a two-sublattice model (Cu, Ni, Ti, Va)0.5(Cu, Ni, Ti, Va)0.5, where Va represents a vacancy and one sublattice is occupied predominantly by Ti and the other by Ni and Cu. Other phases such as B11 based on a TiCu compound and low-temperature phases B19′ and B19 were also described with two-sublattice models with different distribution of atoms on each sublattice. A thermodynamic description of the Ti0.5Ni0.5-Ti0.5Cu0.5 system was obtained from an optimization based on experimental information. The calculated diagram of the pseudobinary Ti0.5Ni0.5-Ti0.5Cu0.5 system at high temperatures exhibits eutectic solidification of liquid and shows satisfactory agreement with experimental data. The phase relations among the B2, B19′, and B19 phases at low temperatures were also assessed on the basis of experimental information from martensitic transformations.

Due to their atomically ultrathin thickness, the development of high-performance transition-metal dichalcogenides (TMDCs) based photodetectors demands device designs distinct from architectures adopted in conventional bulk semiconductor devices. Here, we demonstrate a field-induced Schottky barrier photodiode with three different TMDC materials, WSe2, MoTe2, and WS2. Owing to the high gate efficiency of a high-κ dielectric film, the Schottky barrier at metal contacts is effectively modulated by external bias, giving rise to a strong diode-like rectifying characteristic with high current on/off ratio. The WSe2photodiode shows a linear dynamic range of 112 dB, a responsivity of 0.17 A/W, and response time of 8 ns. When this fast WSe2device is employed for visible light communication data linking, a maximum real-time data transmission rate of 110 Mbps is achieved. Meanwhile, infrared light communication was also realized with a maximum data rate of 30 Mbps using a field-induced MoTe2Schottky barrier photodiode as a light sensor. This work provides a general CMOS-compatible and controllable fabrication strategy for TMDC-based photodetectors.

Experimental information on the transformation temperatures and the thermodynamic properties of the near-equiatomic TiNi alloys is analyzed. Special attention is paid to the estimation of T0temperature from experimental Msand Aftemperatures. The properties of the TiNi low-temperature phase (B19′) are evaluated from selected experimental data by using a two-sublattice model. The Ti-Ni phase diagram including the B19′ phase is then calculated. It reveals that the equiatomic TiNi parent phase (B2) remains stable from high temperatures until 370 K, and then the B19′ phase becomes thermodynamically stable as a linear compound under 370 K. Thermodynamic quantities such as the T0temperature and transformation enthalpy are also calculated and compared with experimental data. Further, the Mstemperature is predicted and compared with data from different sources.