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Summary: The regular operation of the subway negatively impacts the occupants of super high‐rise multi‐tower buildings located on over‐depot (MBLO), causing undesirable vibrations. To save engineers time and computational cost, an improved one‐dimensional impedance model of super high‐rise MBLO is established to predict undesirable vibration in the design phase and devise measures to enhance human comfort. The stiffness factor of the thick plate of a large chassis is introduced, and the impedance relationships of coupled beam and floor based on the equivalence of mass and bending stiffness are considered for an improved one‐dimensional impedance model. The vibration response of multi‐story buildings and super high‐rise MBLO is predicted by an improved one‐dimensional impedance model and compared with field measurements and experimental results, respectively. The results show that the vibration transmission law of super high‐rise MBLO can be more accurately predicted when the stiffness factor of thick plates and the impedance relationships of coupled beam and floor are adopted in an improved one‐dimensional impedance model of super high‐rise MBLO. [ABSTRACT FROM AUTHOR]

Rural domestic sewage, originating from human activities that involve the extraction and utilization of natural resources, is an inherent component of the ecological cycle in nature. Therefore, its disposal methods should align and harmonize with the laws governing nature's evolutionary processes. This study conducted a comprehensive investigation on the domestic sewage facilities in representative villages located within the water source protection area of the middle route of the South-to-North Water Diversion Project. Taking Village A's domestic sewage treatment station as a case study, an analysis was performed to assess its operational status and identify existing issues. The consideration of rural domestic sewage treatment should encompass factors such as the generation and discharge of household wastewater, the characteristics of water quality, discharge regulations, the natural and social environment, as well as post-completion operations and maintenance modes. We also proposed source reduction measures for the reuse of gray water in domestic sewage treatment in Village A, along with integrated treatment approaches involving biochemical treatment, landscape integration, and farmland irrigation for black water. These measures not only achieve effective treatment outcomes but also foster harmonious coexistence between humans and nature. Moreover, they align with the principles of ecological civilization while considering rural revitalization and promoting green agricultural development. [ABSTRACT FROM AUTHOR]

In recent years, wind energy has begun to receive a significant amount of attention as clean energy is utilised and demanded in large quantities, resulting in a sharp increase in the use of wind turbines. The demand for wind turbines has gradually risen due to the clean and recyclable nature of wind energy. The current blade life of wind turbines in China is about 20 years, which means that the disposal of obsolete used blades can become a difficult problem in the future. Therefore, this study is of great significance to explore the regeneration performance of the blades after recycling and disposal. In this paper, wind turbine blades were mechanically recycled into recycled macrofibres, which were added to concrete as a reinforcing material to make wind impeller fibre concrete (WIC), and the three proportion ratios of 1%, 1.5%, and 2% were explored to compare the performance. The performance of WIC was also evaluated and its performance was compared to that of glass fibre concrete (GC). In addition, the material physical properties of second-generation recycled aggregate concrete (RAC) based on WIC were explored. The strength and peak strain variations and their causal mechanisms were analysed both macroscopically and microscopically by means of the classical mechanical tests (compression and bending tests), SEM, and XRD. The results show that the compressive strength of WIC was negatively correlated with the fibre content and increased by 6.04–18.12% compared to that of ordinary concrete (OG), with a maximum of 19.25 MPa; the flexural strength was positively correlated with the fibre content, with an increase of 5.37–18.5%. The microstructural analysis confirmed the macroscopic results and the intrinsic model better validated the experimental results. [ABSTRACT FROM AUTHOR]

The quartz sand-enhanced coagulation (QSEC) is an improved coagulation method for treating water, which uses quartz sand as a heavy medium to accelerate the sedimentation rate of flocs and reduce the sedimentation time. The factors that influence the QSEC effect and can be controlled manually include the quartz sand dosage, coagulant dosage, sewage pH, stirring time, settling time, etc., and their reasonable setting is critical to the result of water treatment. This paper aimed to study the optimal conditions of QSEC; first, single-factor tests were conducted to explore the optimal range of influencing factors, followed by response surface methodology (RSM) tests to accurately determine the optimum values of significant factors. The results show that the addition of quartz sand did not improve the water quality of the coagulation treatment, it took only 140 s for the floc to sink to the bottom, and the sediment volume only accounted for 12.2% of the total sewage. The quartz sand dosage, the coagulant dosage, and sewage pH all had a significant impact on the coagulation effect, and resulted in inflection points. A QSEC-guiding model was derived through RSM tests, and subsequent model optimization and experimental validation revealed the optimal conditions for treating domestic sewage as follows: the polyaluminum chloride (PAC) dosage, cationic polyacrylamide (CPAM) dosage, the sewage pH, quartz sand dosage, stirring time, and settling time were 0.97 g/L, 2.25 mg/L, 7.22, 2 g/L, 5 min, and 30 min, respectively, and the turbidity of the treated sewage was reduced to 1.15 NTU. [ABSTRACT FROM AUTHOR]

The distributed energy power system needs to provide sufficient and flexible computing power on demand to meet the increasing digitization and intelligence requirements of the smart grid. However, the current distribution of the computing power and loads in the energy system is unbalanced, with data center loads continuously increasing, while there is a large amount of idle computing power at the edge. Meanwhile, there are a large number of real-time computing tasks in the distributed energy power system, which have strict requirements on execution deadlines and require reasonable scheduling of multi-level heterogeneous computing power to meet real-time computing demands. Based on the aforementioned background and issues, this paper studies the real-time service scheduling problem in a multi-level heterogeneous computing network of distributed energy power systems. Specifically, we consider the divisibility of tasks in the model. This paper presents a hierarchical real-time task-scheduling framework specifically designed for distributed energy power systems. The framework utilizes an orchestrating agent (OA) as the execution environment for the scheduling module. Building on this, we propose a hierarchical selection algorithm for choosing the appropriate network layer for real-time tasks. Further, we develop two scheduling algorithms based on greedy strategy and genetic algorithm, respectively, to effectively schedule tasks. Experiments show that the proposed algorithms have a superior success rate in scheduling compared to other current algorithms. [ABSTRACT FROM AUTHOR]

The construction of water-saving renovation projects can bring substantial benefits to the development of agriculture, but it may also be accompanied by negative impacts, especially in a large-scale irrigation district. Hence, there is always controversy, and it is vital and necessary to investigate the effectiveness of water-saving renovation. In this study, the Yahekou irrigation district, one of the largest districts in China, is selected as the case to explore the beneficial influence and adverse impact. Kriging interpolation, Pearson correlation analysis, and linear regression analysis are employed to study the temporal evolution, spatial distribution, and domain influencing factors. The results show that the water-saving renovation project in the Yahekou irrigation district had significant water-saving benefits during the period of 1998–2021, and the average annual water use of the irrigation district decreased by 61%. Canal lining is an important influencing factor for the decrease in irrigation water use, with a correlation coefficient of −0.538, B of −18.669, and R2 of 0.290. Furthermore, the water-saving renovation of irrigation districts is not the dominant reason for changes in groundwater depth. Meanwhile, the groundwater depth below ground level (the level DBGL) in the irrigation district increased by 82%. The combined effects of atmospheric precipitation, canal lining, river sand mining, and groundwater exploitation have led to a sustained increase in groundwater depth in the study area. The results obtained from this study can provide valuable and scientific reference for agricultural water resource management over the large-scale irrigation district. This article focuses on the impact of water-saving renovation on ecological and technical indicators such as water use and the groundwater DBGL. However, the impact of water-saving renovation in irrigation districts is multifaceted; subsequent research can explore the impact of water-saving renovation projects on society and the economy. [ABSTRACT FROM AUTHOR]

Constructing π‐conjugated polymer structures through covalent bonds dominates the design of organic framework photocatalysts, which significantly depends on the selection of multiple donor‐acceptor building blocks to narrow the optical gap and increase the lifetimes of charge carriers. In this work, self‐bipolarized organic frameworks of single aromatic units are demonstrated as novel broad‐spectrum‐responsive photocatalysts for H2O2 production. The preparation of such photocatalysts is only to fix the aromatic units (such as 1,3,5‐triphenylbenzene) with alkane linkers in 3D space. Self‐bipolarized aromatic units can drive the H2O2 production from H2O and O2 under natural sunlight, wide pH ranges (3.0‐10.0) and natural water sources. Moreover, it can be extended to catalyze the oxidative coupling of amines. Experimental and theoretical investigation demonstrate that such a strategy obeys the mechanism of through‐space π‐conjugation, where the closely face‐to‐face overlapped aromatic rings permit the electron and energy transfer through the large‐area delocalization of the electron cloud under visible light irradiation. This work introduces a novel design concept for the development of organic photocatalysts, which will break the restriction of conventional through‐band π‐conjugation structure and will open a new way in the synthesis of organic photocatalysts. [ABSTRACT FROM AUTHOR]

This paper demonstrates a simple method to improve the field emission of graphene sheets (GSs) by coating them with thin films of rare earth oxides. The rare earth oxide films are coated on GS using drop coating, without changing the surface morphology, resulting in a remarkable improvement in the field emission properties of GSs. The field emission property of GSs is tunable and can be optimized by applying various rare earth oxide films at the appropriate level. It is found that the turn-on field of GSs is reduced from 4.2 V/mm to 1.7 V/mm by Gd2O3 and to 2.2 V/mm by La2O3. The threshold field of GS is also reduced from 7.8 V/mm to 3.4 V/mm and 4.8 V/mm, respectively. Field emission results indicate that the improvement is due to the low work function surface and more effective emission sites generated around the GS surface after coating. The field emission test and the emission pattern suggest that the field emission performance of GS can be significantly enhanced through the application of La2O3 and Gd2O3 coating, as well as by optimizing the concentration of rare earth oxides in the coating. Hence, the rare earth-coated GS can serve as a potential field emitter. [ABSTRACT FROM AUTHOR]

This study focuses on the vibration control effect of the spring vibration isolation system (SVIS) on a super high-rise building located on the subway (BLS) and the transmission mechanism of vibration in super high-rise BLS. Firstly, the 1:35 scale shaking table test model of super high-rise BLS is designed, the rationality of the shaking table test model is verified, and the shaking table test is implemented. Secondly, the finite element model (FEM) is established and verified based on the results of the shaking table test. Finally, based on verified FEM, the vibration control effect of SVIS on super high-rise BLS and the vibration transmission mechanism of super high-rise BLS is analyzed. The results show that the vibration response of the BLS show amplification trend along the height direction. The amplification of vibration response of BLS is effectively controlled by SVIS. The higher the floor, the greater the reduction coefficient, and the better the control effect. The reduction coefficient above 10F is mainly distributed above 0.80 due to the SVIS. The BLS equipped with the SVIS maintains the degree of Z-direction vibration and 1/3 octave vibration acceleration level that is within the limits stipulated by the specifications. The first-order vertical frequency of BLS equipped with the SVIS is adjusted from 65 Hz to 8 Hz, far from the favorable frequency range of the subway wave. [ABSTRACT FROM AUTHOR]

Constructing π‐conjugated polymer structures through covalent bonds dominates the design of organic framework photocatalysts, which significantly depends on the selection of multiple donor‐acceptor building blocks to narrow the optical gap and increase the lifetimes of charge carriers. In this work, self‐bipolarized organic frameworks of single aromatic units are demonstrated as novel broad‐spectrum‐responsive photocatalysts for H2O2 production. The preparation of such photocatalysts is only to fix the aromatic units (such as 1,3,5‐triphenylbenzene) with alkane linkers in 3D space. Self‐bipolarized aromatic units can drive the H2O2 production from H2O and O2 under natural sunlight, wide pH ranges (3.0‐10.0) and natural water sources. Moreover, it can be extended to catalyze the oxidative coupling of amines. Experimental and theoretical investigation demonstrate that such a strategy obeys the mechanism of through‐space π‐conjugation, where the closely face‐to‐face overlapped aromatic rings permit the electron and energy transfer through the large‐area delocalization of the electron cloud under visible light irradiation. This work introduces a novel design concept for the development of organic photocatalysts, which will break the restriction of conventional through‐band π‐conjugation structure and will open a new way in the synthesis of organic photocatalysts. [ABSTRACT FROM AUTHOR]