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Under the background of “dual carbon”, new energy sources have begun to be connected to the grid on a large scale. However, the randomness and volatility of new energy generation significantly impact the power grid, making it urgent to build a new power system. As the cornerstone of the power system, traditional thermal power will transform into a basic security and system regulatory power supply, providing reliable capacity, peak regulation and frequency modulation and other auxiliary services. The flexible transformation of thermal power units has become an inevitable choice. The phased objectives, difficulties, and challenges of building a new power system were analyzed, along with the problems encountered in the flexible transformation of thermal power units at the present stage. Combined with thermal power operation data, the technical ways of configuring energy storage equipment for thermal power units were analyzed. The research shows that there are several issues in building a new power system, such as power system instability, difficulties in transforming traditional thermal power, high energy consumption, and environmental pressures. The flexibility transformation of thermal power units faces challenges such as insufficient peak regulation capacity, high operation costs, slow load response, high operation energy consumption, safety concerns, etc. The integration of thermal power and energy storage will bring better economic and environmental benefits.

AIM:To investigate the influencing factors of abnormal telangiectasia secondary to diabetic retinopathy(DR).METHODS: Prospective studies. A total of 153 cases(240 eyes)with DR treated in our hospital from January 2021 to January 2023 were selected to analyze the risk factors of abnormal telangiectasia secondary to DR and its predictive efficacy.RESULTS: The patients were divided into dilated group(77 eyes of 40 cases)and non-dilated group(163 eyes of 113 cases)according to whether they had secondary abnormal telangiectasia. There were significant differences in diabetic macular edema, hard exudates grade and fasting blood glucose level between the two groups(P

Energy storage technology is the key technology to building a new power system with new energy as the main body and an important guarantee to maintain the reliable and stable operation of microgrids. Existing theoretical research and projects at home and abroad are mainly concentrated on single-level cascaded energy storage systems. The power module and battery system are connected with passive devices. The structure is simple without enough control degrees of freedom. In the meantime, aiming at an unbalanced state of charge (SOC) of the battery in cascaded energy storage, the existing intra-phase SOC balance control strategy has disadvantages such as poor adaptability to different load ratesand possible over-modulation in case of extreme imbalance. Based on the double-stage cascaded energy storage system, its overall control strategy and the inter-phase and intra-phase SOC balance strategies are illustrated in this paper. An adaptive intra-phase state of charge balance strategy is proposed and its design principle of the balanced control parameters is explained in detail. The adaptability and balance effect of the cascaded energy storage system under different working conditions such as light loads and heavy loads are improved effectively. Finally, the feasibility and effectiveness of the proposed control strategy are verified by simulation, thus providing theoretical reserves and technical support for project implementation.

The recycling of industrially emitted CO2 is an urgent environmental task. The electrochemical reduction of CO2 into valuable chemical products presents an attractive approach. However, due to the inherent high chemical stability of CO2 molecules and the complex sequence of multiple electron and proton transfer steps involved in the CO2 reduction reaction (CO2RR), current electrocatalytic systems commonly face challenges such as low CO2 conversion rates and energy utilization efficiency, limited current density, and short electrode lifespan. Herein, we adopt a simple three-step process involving in situ chemical etching, thermal oxidation, and electrochemical reduction to construct bismuth nanosheets (Bi NSs) with abundant lattice dislocations on copper foam, and introduce nanobubble technology to enhance the CO2RR process. In an H-type cell with flowing electrolyte, our Bi NSs/CF electrode achieved a remarkable formate Faradaic efficiency (FEformate) of 95.36% at a low applied potential of −1.08 V vs. RHE (reversible hydrogen electrode), along with a significant formate partial current density (Jformate) of ∼38 mA cm−2 and an energy efficiency of ∼60%. Even within a wider operating window (−0.78 to −1.18 V), the FEformate remained at a high level (>91%). Importantly, the application of nanobubble technology increased the CO2 conversion rate by nearly fivefold. Further density functional theory calculations confirmed that the Bi NSs with lattice dislocations on the Bi NSs/CF surface can effectively stabilize the *OCHO intermediate, thereby achieving high activity and selectivity for the CO2RR. This work highlights the significant roles of nanobubble technology, size-dependent catalysis, and crystal defect engineering strategies in the field of electrocatalysis, elucidating the activity sources of the developed catalyst in the electrochemical CO2 reduction process, and providing valuable insights for the design and development of high-performance electrocatalytic systems for the CO2RR and other applications. [ABSTRACT FROM AUTHOR]

In order to reduce the large amount of energy consumption and waste gas emission during the construction of nonsolidified rubber asphalt waterproof coating, the related factors affecting its viscosity were studied in order to reduce its construction temperature. Based on the rotating viscosity test method of blochfield, raw materials such as rubber powder, SBS, SBR, asphalt and oil, filler and APAO were selected as research objects, and the influence of the above raw materials on the viscosity of non-curing rubber asphalt waterproof coating was analyzed experimentally. Results show that without adding rubber powder, reduce the amount of SBS and SBR modified agents, adjust the asphalt oil ratio to 1-3, asphalt and oil of the curing rubber asphalt waterproof coating viscosity by 1340 mPa⋅s when 180 °C reduced to 990 mPa⋅s when 130 °C, make the construction temperature of waterproof coating 30 °C lower, and its extensibility and creep is better. [ABSTRACT FROM AUTHOR]

Accurate wind speed forecasting (WSF) plays a pivotal role in anticipating the power output of wind farms. Nevertheless, the stochastic and variable nature of wind speed presents a significant challenge in achieving accurate WSF. Hence, this study proposes a novel 4D high-resolution system, Windformer, for wind speed vector forecasting (WSVF). Windformer combines the ability of convolutional neural networks (CNNs) for feature extraction and transformers based on attention mechanisms for information fusion. In the Windformer, the input and output layers are mainly composed of 3D CNNs. The input layer is employed for feature extraction and information compression, while the output layer is tasked with recovering the WSV field. The key components of the model consist of encoders and decoders built upon temporal shifted window multi-head self-attention. This architecture is capable of effectively integrating spatio-temporal information. Trained on 39 years of regional reanalysis data, Windformer obtains the most accurate forecast results compared to 5 WSF baseline models. Most importantly, within the next 6 hours, Windformer demonstrates higher accuracy compared to the High-Resolution Deterministic Forecast (HRES) from the European Centre for Medium-Range Weather Forecasts (ECMWF). • Windformer enables high-resolution regional-level wind speed vector predictions. • Windformer surpasses baseline models in forecasting wind speeds for the upcoming 1 to 48 h. • Training Windformer only requires two RTX4090 GPUs. • Windformer shows an MAE about 0.05–0.2 m/s lower than HRES within the next 6-hour wind speed forecast. • Windformer efficiently handles spatio-temporal information using temporal shifted window multi-head self-attention. [ABSTRACT FROM AUTHOR]

Objective: Neointimal hyperplasia is the primary mechanism underlying atherosclerosis and restenosis after percutaneous coronary intervention. Ketogenic diet (KD) exerts beneficial effects in various diseases, but whether it could serve as non-drug therapy for neointimal hyperplasia remains unknown. This study aimed to investigate the effect of KD on neointimal hyperplasia and the potential mechanisms., Methods and Results: Carotid artery balloon-injury model was employed in adult Sprague-Dawley rats to induce neointimal hyperplasia. Then, animals were subjected to either standard rodent chow or KD. For in-vitro experiment, impacts of β-hydroxybutyrate (β-HB), the main mediator of KD effects, on platelet-derived growth factor BB (PDGF-BB) induced vascular smooth muscle cell (VSMC) migration and proliferation were determined. Balloon injury induced event intimal hyperplasia and upregulation of protein expression of proliferating cell nuclear antigen (PCNA) and α-smooth muscle actin (α-SMA), and these changes were significantly ameliorated by KD. In addition, β-HB could markedly inhibit PDGF-BB induced VMSC migration and proliferation, as well as inhibiting expressions of PCNA and α-SMC. Furthermore, KD inhibited balloon-injury induced oxidative stress in carotid artery, indicated by reduced ROS level, malondialdehyde (MDA) and myeloperoxidase (MPO) activities, and increased superoxide dismutase (SOD) activity. We also found balloon-injury induced inflammation in carotid artery was suppressed by KD, indicated by decreased expressions of proinflammatory cytokines IL-1β and TNF-α, and increased expression of anti-inflammatory cytokine IL-10., Conclusion: KD attenuates neointimal hyperplasia through suppressing oxidative stress and inflammation to inhibit VSMC proliferation and migration. KD may represent a promising non-drug therapy for neointimal hyperplasia associated diseases.