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The prefabricated construction has rapidly transformed the building industry, and achieveing the swift demolding of component is fundamental for the rapid development of prefabricated industry. The effects of sulphoaluminate cement (CSA) at low replacement rate (from 2. 5% to 7. 5% of cement mass) on the early hydration and mechanical properties of Portland cement were studied. Setting time, compressive strength, hydration heat, XRD, TG, and SEM were used to expose to the behind mechanism, providing solutions for the rapid demolding of prefabricated component. The result show that the incorporation of CSA can shorten the setting time of Portland cement, enhance early hydration, and improve early mechanical properties. With the increase of the CSA mass fraction from 2. 5% to 7. 5%, the initial setting time reduces by 30%, 43% and 49% respectively, and the final setting time by 24%, 40% and 46%, respectively. 5% mass fraction of CSA increases the 12 h compressive strength from 5. 2 MPa to 12. 8 MPa, an increase of 169%. Additionally, CSA also improves the later-stage mechanical properties of the system. [ABSTRACT FROM AUTHOR]

It is fundamentally challenging to achieve stable and efficient all‐inorganic perovskite solar cells (PSCs) in ambient air conditions for low‐cost commercial manufacturing, as the crystallinity, surface morphology, and optical activity of all‐inorganic perovskites exhibit high sensitivity to environmental factors such as moisture and illumination. Herein, a dual‐doping strategy is presented to prepare high‐quality dual‐doping CsPbI2Br films under ambient air with relative humidity of 70% (70% RH) by introducing CaCl2 and InCl3 additives into precursor solution. The results from the experiments and calculations reveal that the CaCl2 additive can isolate moisture by forming hydrates at the surface and grain boundary of perovskites. Meanwhile, the addition of InCl3 can significantly improve the optoelectronic properties via the heterovalent substitution of Pb2+ by a small amount of In3+. Moreover, the phase segregation can be significantly suppressed in the dual‐doping CsPbI2Br films owing to decreasing the electron–phonon coupling strength and increasing the activation energy of ion migration. The unencapsulated dual‐doping CsPbI2Br PSC with the power conversion efficiency (PCE) of 15.51% (70% RH) demonstrates high humidity storage and long‐term optical stability, remaining 90% of the original PCE after aging 2400 h under ambient air (50% RH) and 1500 h under continuous illumination, respectively. [ABSTRACT FROM AUTHOR]

Clustered Federated Learning (CFL) leverages the differences among data distributions on clients to partition all clients into several clusters for personalized federated training. Compared with the conventional federated algorithms such as FedAvg, existing methods for CFL require either more communication costs or multi-stage computation overheads. In this paper, we propose an iterative CFL framework with almost the same communication cost as FedAvg in each round based on a novel model distance. Specifically, the model distance measures the discrepancy between the client model and the cluster model so that we can estimate the cluster identities for clients on the server side. The proposed model distance considers class-wise model dissimilarity, which enables us to apply it to multi-class classification even when the labels are non-iid across clients. To calculate the proposed model distance, we introduce two sampling methods which generate samples from feature distributions approximately without accessing the raw dataset. Experimental results show that our method can achieve superior and comparable performance on non-iid and iid data respectively with less communication cost compared with the baselines. [ABSTRACT FROM AUTHOR]

Karst landforms are one of the most typical geographical units with a specific physical process on the earth's surface. The classification of karst landforms is an important aspect for understanding their landform processes and mechanisms. However, influenced by various interior and external forces, karst landforms have an extremely complex surface morphology, increasing the difficulty of their automatic classification. In this study, we considered hydrological features as an important factor in characterizing karst landforms and proposed a method that considers surface flow for karst landform classification. In this method, terrain was reversed for hydrological analysis to achieve the landform units. Then, the watershed boundary of the reversed terrain is extracted by hydrological analysis. The boundary of the karst landform unit is determined by erasing the plain area from the watershed boundary. Thereafter, the graph theory segmentation method is employed to merge the landform units belonging to the same karst landform entity. The proposed approach is validated and applied in two sample karst areas, Fenglin and Fengcong, located in Guilin, China, using digital elevation model data with 30 m spatial resolution. In addition, a comparative analysis is conducted to evaluate the accuracy of the proposed method. The results demonstrated that the typical karst landform units of Fenglin and Fengcong can be effectively classified. The overall classification accuracy is 94.44%. The proposed method produced more reasonable and accurate boundaries compared with the contour tree and terrain feature point methods. Furthermore, the classification results indicate various landform development stages of the karst landform process in the study area. The proposed method considering surface flow characteristics can be further extended to other landform types with highly complex landforms. [ABSTRACT FROM AUTHOR]

Controlling and optimizing the photoactive layer morphology is closely related to the process of exciton dissociation, charge transfer and collection and thus is crucial for building a high-performance polymer solar cell (PSC). Due to the limited solubility of non-halogenated solvents and the strong crystallinity of Y6 acceptors, it is a challenge to optimize the morphology of the Y6-based blend active layer processed by a non-halogenated solvent for achieving a high photovoltaic performance. In this work, we develop a morphology controlling method by applying BTBT and DTBDT as solid additives to regulate the phase separation of the o-xylene-processed PM6:Y6 blend films. The strong crystalline behavior of BTBT and DTBDT can restrict the over-aggregation of Y6 molecules in a low volatility processing solvent during the film formation. The stronger crystallinity and better miscibility with Y6 of BTBT over DTBDT lead to a favorable effect in facilitating the formation of a nanoscale bicontinuous interpenetrating network in the PM6:Y6 active layer. As a result, the o-xylene-processed PM6:Y6-based PSC treated with BTBT and DTBDT additives shows an enhanced power-conversion efficiency (PCE) of 16.37% and 14.40%, respectively, as compared to the control device (PCE = 10.25%) using 1-chloronaphthalene as a solvent additive. [ABSTRACT FROM AUTHOR]

Many evidences have shown that synchronization takes a key role in brain functions, but most of its theoretical studies are so far only focused on the global brain network. However, it is well-known that all the cognitive tasks are performed by individual local cognitive subnetworks but not the global brain network, thus it is necessary to study the synchronization of local brain networks. We here focus on this problem by considering the synchronization transition of all the 63 local subnetworks of a real brain network and interestingly find that these local networks of cortical regions may show a completely different synchronization transition from that of global brain network, i.e., non-monotonic order parameter with folding. Moreover, we find that the forward and backward processes show different synchronization transitions, such as one being the first-order synchronization transition and the other being the second-order synchronization transition, and even amplitude death, depending on the different topologies of local networks. By extensive numerical simulations, we show that the amplitude death is prefer to occur in the local networks with larger size but not prefer to occur in the local networks with smaller size. A brief theoretical analysis is presented to explain the mechanism of amplitude death. [ABSTRACT FROM AUTHOR]

A recent article in Solar RRL discusses a dual doping strategy using metal chlorides to enhance the stability and performance of all-inorganic perovskite solar cells. The researchers used CaCl2 and InCl3 additives to improve the phase stability and photoelectric properties of CsPbI2Br films. The resulting solar cells demonstrated high humidity storage and long-term optical stability, retaining 90% of their original power conversion efficiency after aging for 2400 hours under ambient air (50% relative humidity) and 1500 hours under continuous illumination. This research provides valuable insights for the development of more stable and efficient solar cell technologies. [Extracted from the article]

Perovskite Solar Cells In article number 2400216, Feng Hong, Fei Xu, and co‐workers report a dual doping strategy with CaCl2 and InCl3 additives to improve the phase stability and photoelectric properties of CsPbI2Br films. Thus, the unencapsulated dual doping perovskite solar cell exhibits high humidity storage and long‐term optical stability, remaining 90% of the original power conversion efficiency after aging 2400 hours under ambient air (50% relative humidity) and 1500 hours under continuous illumination, respectively. [ABSTRACT FROM AUTHOR]

Soil microorganisms promote the recovery of contaminated soil by influencing the cyclic transformation of various substances. In this study, we investigated the impact of mercury pollution on the structure, composition, and main populations of soil microbial communities using a high-throughput sequencing method and observed that mercury pollution significantly influenced the diversity, structure, and distribution pattern of microbial communities. Furthermore, during mercury pollution, the Shannon and Chao indices decreased for the bacterial communities and increased for the fungal communities. Mercury pollution mainly reduced the relative abundances of Proteobacteria (16.2–30.6%), Actinomycetes (24.7–40.8%), and other dominant bacterial phyla. The relative abundance of Ascomycota decreased by 17.4% and 16.7% in alkaline and neutral soils, respectively, whereas the relative abundance of unclassified_k_Fungi increased by 26.1% and 28.6%, respectively. In acidic soil, Ascomycota increased by 106.3% and unclassified_k_Fungi decreased by 71.2%. The results of redundancy and correlation analyses suggested that soil microbial diversity was significantly correlated with soil properties such as pH, cation exchange capacity, soil organic carbon, and total nitrogen (p < 0.05) under different treatments. Our findings highlight the impact of Hg pollution on soil microbial communities, thereby providing a theoretical foundation for the bioremediation of soil Hg pollution. [ABSTRACT FROM AUTHOR]

To probe into the effects of nitrogen (N) fertilizer application strategies on the effects of mercury(Hg)-contaminated soil remediation aiming at clear-cut crop-safe measures, pot experiments were conducted to determine soil properties, microbial communities, and eight experimental treatments were carried out including four kinds of N application strategies respectively in acid and alkaline soils: (1) GK, SK (blank control group); (2) GA, SA (applying readily available N-fertilizer); (3) GS, SS (applying slow-release N-fertilizer); and 4) GB, SB (applying slow-release N-fertilizer plus biochar). The experimental results showed that in contrast with the control group (GK, SK), N fertilization could reduce Hg content in acid soil by 20.47% to 81.60% and 23.38% to 75.74% in alkaline soil; comparing with group GA,SA, GS,SS showed reduction of soil Hg content by 75.96% and 69.86% (in acid soil and alkaline soil), respectively. It was worthwhile to note that the treatment using biochar (GB, SB) had no notable effects on the remediation of Hg contaminated soil, compared with the treatment using slowrelease N fertilizer (GS, SS). In contrast with other treatments, slow-release N fertilizer with biochar considerably impacted the soil microbial community structure, i.e. the microbial abundance of acidic soil increased by 6.23% and the diversity decreased by 11.36%, while these two groups in alkaline soil both showed a downward trend, with a decrease of 17.69% and 16.81% respectively. In regard to the investigation on Hg in leaks, in contrast with the control group, all the N-fertilizer application groups showed that Hg content in leeks edible parts and roots decreased by 20.38% to 66.46% and 20.76% to 35.22% in acid soil, respectively. However, in alkaline soil only slow-release N fertilizer plus biochar group (GB, SB) could remarkably reduced Hg content in edible parts and roots, and compared with group slow-release N fertilizer (GS, SS), declined by 45.05% and 28.15%, respectively. Moreover, according to Spearman correlation analysis, soil pH, organic matter and Hg content were the critical factors affecting the bacterial community. Accordingly, the application of slow-release N-fertilizer was the best choice to diminish soil Hg pollution, and combined applications of slow-release N-fertilizer plus biochar can reduce Hg content in soil and crops; at the same time, significantly boost the microbial abundance specially in acidic soil. In conclusion, the experiments achieved theoretical basis for using different N-fertilizer application strategies to alleviate soil Hg pollution, meantime, probing into the effects of slow-release N-fertilizer plus biochar. [ABSTRACT FROM AUTHOR]

With the development of the 5G mobile Internet, cloud computing, Internet of Things, and other cutting-edge technologies, the era of big data has quietly arrived. The purpose of this paper is to explore the feasibility of the application of new technologies for music teaching in the era of big data in the context of the rapid development of science and technology in the information society, to enlighten and lead music teachers to apply the spontaneous and conscious awareness of new media and fully apply the new achievements of science and technology in the information society for future music classroom teaching, and to analyze the mode, method, trend, characteristics, advantages, and disadvantages of music teaching in the new media environment. The aim is to analyze the advantages and shortcomings of music teaching in colleges and universities and to find solutions and future development strategies for them so that in the future, the 5G Internet can better serve music lovers and better contribute to the cause of music education in colleges and universities. New media, as a product of constantly updated information technology, provides powerful data support for the development of various fields, and the education industry also needs new media to boost the rapid development of education information technology, which of course includes college music teaching. The effective integration of new media technology into the college music classroom can improve the classroom efficiency of music teaching with rich and diverse teaching resources and flexible teaching forms. [ABSTRACT FROM AUTHOR]

In China, promoting harmless blackwater treatment and resource utilization in rural areas is a priority of the "toilet revolution". Exploring the effects of blackwater application in arid areas on soil nitrogen losses can provide a basis for more effective water and fertilizer management. This study analyzed nitrogen leaching and maize yield under blackwater application in the summer maize season of 2020. A total of 5 treatments were used: no fertilizer, single chemical fertilizer application (CF), single blackwater application (HH), and combined chemical fertilizer and blackwater application ratios of 1:1 (CH1) and 2:1 (CH2). The total nitrogen leached from the fertilization treatments was 53.14–60.95 kg·ha−1 and the leached nitrate nitrogen was 34.10–40.62 kg·ha−1. Nitrate nitrogen accounted for 50–62% of the total leached nitrogen. Compared with blackwater treatments, nitrate nitrogen moved into deeper soil layers (80–100 cm depth) during the CF treatment. Compared with CF, HH significantly reduced the maize yield by 24.39%. The nitrogen surplus of HH was higher than that of other fertilizer treatments. Considering nitrogen leaching, maize yield, and economic benefits, the CH2 treatment presented the optimal results. These findings address knowledge gaps and assist in guiding policy-makers to effectively promote China's "toilet revolution". [ABSTRACT FROM AUTHOR]

Replacing chemical fertilizers with human waste for vegetable planting is a traditional, economical, and environmentally friendly waste resource utilization strategy. However, whether the human waste substitute strategy can improve soil fertility and increase crop yield and quality compared to the simple application of chemical fertilizers is still unclear, especially under acidic and alkaline soil conditions. In this study, we studied the effects of different ratios of human waste (urine and feces) to chemical fertilizer on the crop yield, crop quality, soil fertility, and soil chemical parameters in alkaline Cambisols and acidic Alisols cultivated with water spinach (Ipomoea aquatica Forssk.). The application variants of human waste and chemical fertilizer were as follows: (i) Control, no fertilization (CK), (ii) human waste application (HW), (iii) chemical fertilizer application (CF), (iv) 1/3 human waste to chemical fertilizer (P1), and (v) 2/3 human waste to chemical fertilizer (P2). Human waste application increased the total nitrogen, available phosphorus, available potassium, organic matter, NO3−-N, and conductivity in soil, enhanced soil enzyme activity, slowed down soil acidification, and increased the yield, soluble sugar, and vitamin C contents of the water spinach while reducing its nitrate content. Our findings indicate that human waste substitution improved soil fertility while reducing the potential risks of soil acidification, salinization, and human exposure to nitrates. These findings may be applied to increase vegetable production and quality, improve the soil environment, and increase the utilization of human waste as a valuable resource. [ABSTRACT FROM AUTHOR]