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High entropy alloys (HEAs) are a highly promising class of materials for electrocatalysis as their unique active site distributions break the scaling relations that limit the activity of conventional transition metal catalysts. Existing Bayesian optimization (BO)-based virtual screening approaches focus on catalytic activity as the sole objective and correspondingly tend to identify promising materials that are unlikely to be entropically stabilized. Here, we overcome this limitation with a multiobjective BO framework for HEAs that simultaneously targets activity, cost-effectiveness, and entropic stabilization. With diversity-guided batch selection further boosting its data efficiency, the framework readily identifies numerous promising candidates for the oxygen reduction reaction that strike the balance between all three objectives in hitherto unchartered HEA design spaces comprising up to 10 elements.

Abstract Subway stations are important components of subway system planning and urban rail transit where passengers can board, alight, transfer, or wait. With an increase in urban passenger flow, subway stations must meet greater transfer‐space demands commensurate with growing station structure sizes. In this study, the field‐monitoring and analysis method was adopted to investigate the Huaxing Street Station of the Chengdu Metro Line 19 project and explore the temperature‐variation rule in the process of mass‐concrete pouring in the station floor. Based on an ABAQUS large‐finite‐element calculation programme and secondary development of damage and failure research methods, a mechanical model of mass‐concrete pouring in subway‐station floor construction was established. The pouring temperature effect, damage, and failure mechanism of mass‐concrete pouring in subway stations were comprehensively studied. The main results were as follows: (1) the maximum temperature difference between the upper and middle layers of the floor was dominant and reached a peak within 1–3 d after the completion of pouring, and the temperature difference gradually decreased with a decrease in the hydration‐heat reaction. (2) At 0–10 d, the damage ratio of the floor increased by 1.8%, predominantly in the form of longitudinal damage. Within 10–30 d, the damage and failure ratio of the floor increased by 1.86%, primarily in the form of transverse damage and failure. Within 30–40 d, the temperature of the floor stabilized and gradually approached the ambient temperature. The damage and failure ratio of the floor increased by 0.32% at this time. (3) The lower the ambient temperature, the greater was the damage sustained by the floor at different ages, and the ambient temperature had a significant influence on floor damage.

This study proposes to explore the effect of interface angles β on the triaxial mechanical properties of backfill and surrounding rock combined bodies(backfill-rock combined bodies)by conducting a triaxial compression experiment of backfill-rock combined bodies with interface angles β of 0°, 15°, 30°, 45° and 60°. This paper compared and analyzed the mechanical properties, failure characteristics and strength evolution patterns of the combined bodies with different interface angles. The experimental results show that: When β≤30°, the stress-strain curve of the combined bodies can be divided into four stages: pore compaction, elastic deformation, plastic deformation and failure development. Its failure characteristics are mainly compression shear failure of the backfill. With the increase of the interface angles, the combined bodies stress drops steeply after reaching the peak strength, without significant plastic deformation or failure development stage. Its failure characteristics gradually change from compression shear failure inside the backfill to sliding failure along the interface. The peak strength of the combined bodies first increases and then decreases with the increase of the interface angles, and peak strength reaches a maximum value when β=30°. Based on the theory of single weak plane, the interface critical angles for sliding failure of the combined bodies is 57° to 68°. Where β=60°, the combined bodies occurred sliding failure surface along the interface, and the results from theoretical calculation confirm the experimental results.

Objective: To explore whether the novel urine free light chain (uFLC) assay is superior to the traditional urine total light chain (uTLC) assay in quantitative monitoring of urine light chain. Methods: A total of 458 paired samples of blood and were collected from 280 patients (including 153 patients with plasma cell diseases and 137 patients with non-plasma cell diseases) from January 2022 to March 2023 at Ruijin Hospital， Shanghai Jiao Tong University School of Medicine. The positive concordance rates and correlations between the κ value, λ value and κ/λ ratio of uFLC and uTLC assays with the results of urinary immunofixation electrophoresis (uIFE) and serum free light chain (sFLC) were analyzed by Chi-squared test, MeNemar’s test and Spearman correlation coefficient calculation. Result: Among the 102 uIFE positive samples, 88.2% (90/102) of the samples had abnormal uFLC κ/λ ratio, and 87.3% (89/102) had abnormal uTLC κ/λ ratio (P

The power system will gradually step into the era of high percentage of renewable energy， and the shared energy storage can improve the power system resilience and thus effectively consume renewable energy. Since self-built energy storage of users may result in unnecessary sunk costs due to excess capacity and the business model of centralized investment in energy storage user sharing by operators has problems such as high investment costs， centralized operation and non-transparency， a distributed energy storage peer-to-peer transaction model based on blockchain smart contracts is proposed. On the basis of energy storage sharing， a load optimization model of users under the demand response mechanism is established. Finally， a typical daily electric load in spring， summer， autumn and winter in a region of the United States is simulated as an example. The results show that the charging and discharging decision model based on the rational use of shared energy storage can help users to smooth the load curve and realize “low storage and high discharge”， and the shared energy storage model based on blockchain architecture can bring economic benefits to users.

Filling mining is one of the key links in the green mining technology system of coal mines, in view of the transportation technology of the gangue-fly ash based filling slurry during the filling process, parameters such as different mass concentrations, fly ash content, curing temperature and time were set. The rheological tests of the gangue-fly ash based filling slurry under the temperature-time coupling effect were carried out to explore the influence of various parameters on the rheological properties of the slurry. Through orthogonal range analysis, the influence weight of temperature and standing time on the yield stress of the slurry was analyzed, and the rheology under the temperature-time coupling effect parametric regression model was established. The test results show that the mass concentration has a significant effect on the fluidity of the slurry. With the increase of the mass concentration, the linear correlation between the shear stress of the slurry and the shear rate decreases. When the mass concentration is 78%, it has both good fluidity and stability; The increase of the fly ash content will increase the shear stress and the degree of shear thickening. When the amount of fly ash is 85%, the yield stress of the slurry is the largest, followed by the amount of fly ash of 75%, and the amount of fly ash 65% is the smallest; High temperature accelerates the hydration reaction rate of the slurry and enhances the pozzolanic reactivity of fly ash. The curing temperature at 50 ℃ increased by 44.5% and 37.5% respectively compared with 20 ℃ and 35 ℃ when the fly ash was kept for 120 minutes; The setting time has a stronger influence on the yield stress of the slurry than that of temperature. When the fly ash content is 75%, the yield stress of the slurry after standing for 120 minutes at a temperature of 20 ℃ increases by 133.7% compared with that of standing for 0 min; Under different temperature conditions, the yield stress of the slurry increases linearly with standing time, and the degree of fitting is above 0.9. Finally, the yield stress evolution model of the slurry under the temperature-time coupling effect is established. By comparing the calculation results of the theoretical model with the test results, the average error is about 5%, and the fitting effect is good, which can provide a reference for the calculation of the pipeline transportation resistance of the filling pipeline in the coal mine.

The fluctuation and intermittency of wind power have brought about unexpected problems to the optimal operation of the integrated electricity and natural gas systems. Furthermore， it makes the operation management of the integrated system more difficult. Firstly， a typical wind power scenario is obtained by applying a scenario generation method based on a prediction box to characterize the fluctuation of wind power and the correlation between multiple wind farms. Secondly， a day-ahead economic dispatching model of the electrical interconnection system considering the distribution networks， natural gas networks and various coupling elements is developed， and a distributive solution based on the alternating direction method of multipliers （ADMM） is performed. Finally， the effectiveness of the proposed model is verified by taking an electrical interconnection system consisting of an IEEE 33-node distribution network and an IEEE 7-node natural gas network as an example.