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As the largest developing country in the world, China has promised to peak the carbon dioxide emissions before 2030 and achieve carbon neutrality before 2060 to mitigate the greenhouse effect. In the meantime, the electric power industry is playing a key role in achieving this ambitious target through “electricity substitution” and “clean substitution” strategies and constructing the “new type of power system”. Given this background, a specific and detailed model for the electric power supply structure transformation (EPSST) model is proposed in this rapid communication for the first time, which helps to analyse the transformation more reasonably. The proposed EPSST model aims to minimize the total costs for electric power supply structure transformation with the carbon neutrality constraints considered. Besides, the other constraints associated with the construction and retirement of different types of power plants, the balance between power supply and demand, and carbon sinks are also considered. Two scenarios aiming to achieve carbon neutrality before 2060 and 2055 are respectively studied and corresponding analyses for the transformation are also performed. The results show the feasibility of the proposed EPSST model and finally a macroscopic forecast for the future electric power industry is given.

The accurate evaluation of power supply quality in the distribution network is regarded as an important way to improve the power quality of the user side and guide the power quality management of the power grid. Thus, a comprehensive evaluation method of the power supply quality based on the Gaussian cloud (GC) and the technique for order preference by similarity to ideal solution (TOPSIS) is proposed in this work. First, multiple evaluation indexes of the power supply quality are customized based on the measurement data of the distribution network and the power supply work order. On this basis, an index conversion method based on Gaussian cloud is adopted to convert the above indexes into Gaussian cloud distribution. Then, a comprehensive evaluation method of power supply quality based on TOPSIS is proposed for converting the similarity between Gaussian clouds into comprehensive evaluation results. Case study on power supply quality in Zhejiang province, China is employed to demonstrate the effectiveness and rationality of the proposed method. The result shows that the power supply quality can be evaluated by proposed method in an objective and reasonable manner.

The market-oriented transaction of distributed energy resources is regarded as an important way to solve the problem of local distributed energy consumption and improve the operation economy and security of the distribution network. However, the market for distributed power transactions in China is still in the early stage, and there is a lack of effective and reliable transaction mechanisms for standardizing users’ credit behaviors. Therefore, a blockchain-based distributed power transaction mechanism considering credit management is proposed. First, the framework of the distributed power transaction based on blockchain is constructed. On this basis, the process of distributed power transaction considering credit management is designed, which can manage users’ credit behaviors comprehensively from the aspects of market access, bidding mechanism, and trading settlement. Then, the smart contract of distributed power transactions is customized. The effectiveness of the proposed mechanism is illustrated by the simulation results on the platform of Remix IDE.

In future power systems with the characteristics of high-elastic, demand response (DR) is considered to be an essential way for improving system stability and awakening demand-side resources. However, all the DR programs in China are implemented in a centralized model, which is easier for supervision, but hard to deal with the challenges of data credibility, privacy protection, transaction efficiency, and so on. Therefore, a novel blockchain-based framework for the DR program is proposed to deal with the problems. On this basis, the bidding transaction process based on the repeated verification mechanism is designed, and the effectiveness of blockchain in DR is analyzed. Then, the smart contract functions involved in DR bidding transactions and subsidy settlement are customized. The feasibility of the DR bidding mechanism is illustrated by the simulation results on the platform of Remix IDE.

As an advanced information technology, blockchain technology applied in power material supply chain (PMSC) has attracted the broad attention over recent years in order to solve the existing problems and improve the management level. However, the unified evaluation standards and methods, which evaluate the blockchain technology feasibility in PMSC, are still lacking so far. In this paper, the existing problems of PMSC and the characteristics of blockchain technology are analyzed firstly. Moreover, an evaluation index system of blockchain technology feasibility towards PMSC is designed, and the questionnaire method is utilized to obtain the required data from the target group. Furthermore, the fuzzy analytic hierarchy process is used for index weighing and the technique for order preference by similarity to an ideal solution is improved by introducing the strategy of designing target case, which can realize the horizontal comparative evaluation between different evaluation cases and the vertical comparative evaluation between evaluation case and target case. Finally, the case study based on the questionnaire results from State Grid Jiangsu Electric Power Co., Ltd. Material Branch verifies that the index system can provide the decision-making information for the construction and development sequence of PMSC blockchain system. The pilot project of blockchain technology should first be carried out in the business scenario of storage, inspection and distribution of materials because it relative closeness that is 0.8684 is larger than the relative closeness of other selected business scenarios in this case.

China has promised to peak carbon emission before 2030 and to achieve carbon neutrality before 2060 (i.e., “double carbon” goal). Under this background, the emission reduction transformation path of China's electric power industry is studied in this paper. First, several boundary conditions (i.e., assumptions) of electric power structure transformation (i.e., the costs of power generations, the costs of energy storage systems, the developments of carbon sinks, the emission factors, and the quotas of carbon sinks) are given considering the whole society electricity consumption in the future. Second, a transformation path optimization model is established aim to minimize the total cost in the electric power industry. Then, according to the optimization results, the transformation predictions for the power industry under the ''30·60 scenario'' (i.e., the scenario that can achieve carbon peak and carbon neutrality before 2030 and 2060) are analyzed in detail, and are compared with the ones of ''2 °C scenario'' and ''1.5 °C scenario'' defined by IPCC. Furthermore, the influence of different carbon prices on the transformation path is also analyzed. It can be concluded from the simulation results that the ''30·60 scenario'' is a scenario between ''2 °C scenario'' and ''1.5 °C scenario'', and carbon emission can be reduced rapidly under the guidance of high carbon prices.

The need to accelerate the innovation and application of the supply chain has been suggested by the State Council of China. To solve the problem of data isolation caused by privacy protection in the power material supply chain, a data traceability and sharing mechanism based on blockchain is designed in this paper. Firstly, the existing problems of the power material supply chain are introduced, and the applicability of blockchain in the power material supply chain in view of these problems is analyzed. Secondly, blockchain-based power material supply deployment and application structures are proposed. Then, considering the problem of data isolation in the material inspection and distribution links between suppliers and the material company, a data traceability mechanism based on blockchain is designed to provide evidence for the data authenticity and a proxy re-encryption method is used to ensure security and privacy in data sharing. Finally, the effectiveness of the proposed data traceability and sharing mechanism is verified using the Hyperledger Fabric platform for power material case studies. The simulation results show that the combination of proxy re-encryption and blockchain technology in the power material supply chain can confirm the validity of the historical data and keep the private data of the material company confidential, so as to realize the traceability and sharing of the power material supply data.

Copper slag is a kind of huge metallurgical residue with fayalite as the main phase. Due to the oxidation of fayalite to quartz and hematite during sintering process, quartz became the main phase of ceramics when it contained large proportion of copper slag. The internal stress in the ceramic formed due to the change of α to β increases the potential risk of cracks in the quartz cooling process. In this paper, in order to reduce the precipitation of quartz phase, natural diopside rich in CaO and MgO was introduced into the copper slag-based ceramics. A batch of ceramics were prepared with 50 wt.% copper slag and 5 ~ 25 wt.% diopside as raw materials at different sintering temperatures. Evolution of crystals and densification process for the ceramics were investigated through physical property tests, including XRF, XRD, SEM, EDS and FACTSAGE calculation. The results indicated that fayalite particles derived from the slag formed a core-shell structure during the oxidation process, with the inner core dominated by silica and the outer shell enriched by iron oxide. It was observed that MgO and Fe2O3 reacted outside the shell to form mafic spinel (Fe, Mg) Fe2O4, which greatly promoted the reaction of Ca2+ with SiO2 in the core areas to form anorthite. As the amount of diopside increased, more mafic spinel and anorthite formed, while less quartz appeared. The addition of diopside to the ceramic body did not change its initial sintering temperature at 1170°C but significantly improved its bending strength from 35.8 MPa to 50.3 MPa with 5 ~ 20 wt.% addition of diopside, and more diopside would result in excessive flux and over firing.

As the most common type of arrhythmia, atrial fibrillation has proven to be associated with serious adverse cardiovascular and cerebrovascular events, such as heart failure, stroke and myocardial infarction. The global number of patients with atrial fibrillation has exceeded 33 million, and it is estimated to be more than doubled in the next 40 years. Although years of efforts have been made to the research on pathophysiological mechanism, and the exploration of new treatments and improvement of treatments regarding atrial fibrillation, the management of atrial fibrillation is still a difficult problem in clinical medicine, and there is no consensus on the best treatment and the choice of energy source for ablation in atrial fibrillation with the increasing advances made in surgical and catheter ablative techniques. Catheter ablation often requires multiple operations with unsatisfactory success rate and surgical ablation is often associated with high risk of postoperative adverse events. Hybrid ablation, a new treatment recently developed by the joint efforts of cardiac surgeons and electrophysiologists, integrates the merits of catheter ablation and minimally invasive surgical ablation but overcomes the limitations of the two, has proven to be effective in reducing the risk of postoperative adverse outcomes, and considerably efficacious in treating persistent atrial fibrillation, especially long-term persistent atrial fibrillation. We reviewed the advances in atrial fibrillation ablation, and comparatively analyzed existing studies of hybrid ablation, and summarized the advantages and challenges of this treatment, hoping to provide one more option for clinical treatment of atrial fibrillation.