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It is highly desirable to design efficient and stable hydrogen evolution reaction (HER) and oxygen evolution/reduction reaction (OER/ORR) electrocatalysts for the development of renewable energy technologies. Herein, density functional theory (DFT) calculations were conducted to systematically investigate a series of TMNxO4−x-HTT (TM = Fe, Co, Ni, Ru, Rh, Pd, Ir and Pt; HTT = hexahydroxy tetraazanaphthotetraphene) analogs of two-dimensional (2D) conductive metal-organic frameworks (MOFs) as potential electrocatalysts for the HER, OER and ORR. The thermodynamic and electrochemical stability simulations suggest that these designed catalysts are stable. Remarkably, CoO4-HTT, RhN3O1-HTT and IrN3O1-HTT are predicted to be the most promising catalysts for the HER, OER and ORR, respectively, surpassing the catalytic activity of corresponding benchmark catalysts. The volcano plots were established based on the scaling relationship of adsorption Gibbs free energy of intermediates. The results reveal that regulating combinations of metal active centers and local coordination environments could effectively balance the interaction strength between intermediates and catalysts, thus achieving optimal catalytic activity. Our findings not only opt for the promising HER/OER/ORR electrocatalysts but also guide the design of efficient electrocatalysts based on 2D MOFs materials. [ABSTRACT FROM AUTHOR]

Short-term load forecasting (STLF) of heterogeneous multi-agents plays a significant role in smart grid. Faced with special difficulties of multi-agent STLF due to the high heterogeneity, uncertainty and volatility, traditional local methods usually make predictions based on load aggregation or clustering, the complexity of which will rise greatly with the increase of agent types. It has become more and more difficult for traditional methods to meet the STLF demand of smart grid. Meanwhile, global time series forecasting method emerges gradually in many fields, which can make predictions for many agents only by one model with much lower complexity. However, there is few researches on the multi-agent global STLF. This study proposes a global deep-Long Short-Term Memory (LSTM) STLF model based on a pretraining method. The model fully applies the information such as electricity consumption pattern, weather and calendar in a structural and orderly way. The empirical results show that our model can effectively predict the daily load of heterogeneous households, with prediction accuracies of 87.9–90.2% on the test set across various tasks. Compared with the base model, our model achieves an 8.7% higher accuracy with a much faster convergence speed. Furthermore, the fluctuations of accuracy on different tasks are within 2.3%, showing that our model is robust. The superiority of the global method is proved through the comparison with local method in the empirical results. This study is expected to make contribution to global STLF of heterogeneous households and providing experience for the global prediction of heterogeneous time series based on deep-LSTM and pretraining method. [ABSTRACT FROM AUTHOR]

Silicone surfactants have garnered significant research attention owing to their superior properties, such as wettability, ductility, and permeability. Small-molecular silicone surfactants with simple molecular structures outperform polymeric silicone surfactants in terms of surface activity, emulsification, wetting, foaming, and other areas. Moreover, silicone surfactants with small molecules exhibit a diverse and rich molecular structure. This review discusses various synthetic routes for the synthesis of different classes of surfactants, including single-chain, "umbrella" structure, double chain, bolaform, Gemini, and stimulus-responsive surfactants. The fundamental surface/interface properties of the synthesized surfactants are also highlighted. Additionally, these surfactants have demonstrated enormous potential in agricultural synergism, drug delivery, mineral flotation, enhanced oil recovery, separation, and extraction, and foam fire-fighting. [ABSTRACT FROM AUTHOR]

Next generation power system needs dielectrics with increased dielectric energy density. However, the low energy density of dielectrics limits their development. Here, an asymmetric trilayered nanocomposite, with a transition layer (TL), an insulation layer (IL), and a polarization layer (PL), is designed based on poly(vinylidene fluoride)-polymethyl methacrylate (PVDF-PMMA) matrix using KNbO3 (KN) and TiO2 (TO) as the nanofillers. The morphology and defect control of the two-dimensional nano KN and nano TO fillers are realized via a hydrothermal method to increase the composite breakdown strength (Eb) and the composite energy density (Ue). The asymmetric trilayered structure leads to a gradient electric field distribution, and the KN and TO nanosheets block charges transfer along z direction. As a result, the development path of the electrical trees is greatly curved, and Eb is effectively improved. And the Ue value of the nanocomposites reaches 17.79 J·cm−3 at 523 MV·m−1. On the basis, the composite Ue is further improved by defect control in TO nanosheets. The nanocomposite KN/TO/PVDF-PMMA containing TO with less oxygen vacancy concentration (calcined at oxygen atmosphere) acquires a high Ue of 21.61 J·cm−3 at 548 MV·m−1. This study provides an idea for improving the energy storage performance by combining the design of the composite dielectric structure and the control of nanofillers' defect and morphology. [ABSTRACT FROM AUTHOR]

Environmentally friendly lead-free dielectric ceramics have attracted much attention due to their high power density, rapid discharge rate and excellent dielectric stability. In this study, the joint strategy of composition design and morphology design is proposed to improve the energy storage performance of Sr0.7Bi0.2TiO3@Ba0.7Ca0.3TiO3 (SBT@BCT) composite ceramics. The SBT@BCT composite ceramics were prepared by coating BCT on the surface of SBT powders in sol–gel process. The results show that an appropriate BCT content can result in the coexistence of the tetragonal and orthogonal nanodomains, reduce the sintering temperature, and reasonably control the grain scale, thus improving the effective polarization, breakdown strength and temperature stability. When BCT coating is 15 mol%, the polarization maximum of SBT@BCT ceramics is 23.9 μC/cm2 under an applied electric field of 238 kV/cm, the discharged energy density Wrec is 2.31 J/cm3, and the energy storage efficiency is 82%, with a relatively high dielectric constant of 2735 and low dielectric loss of 0.019. The stability deviation of Wrec is within 15% in the range of 20 to 150 °C, and superior dielectric temperature stability (|Δε/ε20 °C|≤ 15%) is measured from − 60 to 120 °C. The results demonstrate that SBT@BCT lead-free ceramics have potential applications for high temperature energy storage capacitors. [ABSTRACT FROM AUTHOR]

Traditional antifouling agents usually have a certain toxic effect on marine environments and non-target organisms. In this study, Dictyophora indusiata polysaccharide (DIP) was applied as a natural antifouling surface modifier to prepare the surface coating for marine antifouling. Three DIP coatings were prepared: D. indusiata spore polysaccharide (DISP), D. indusiata volva polysaccharide (DIVP), and D. indusiata embryonic body polysaccharide (DIEP). The antifouling, tribological, and anticorrosion behavior of the coatings were examined. Results revealed that the three kinds of DIP coatings had excellent antifouling properties, which could effectively prevent the adhesion of Chlorella and the attachment of water-based and oily stains on the surface. Additionally, the coatings showed great mechanical stability and could maintain an extremely low coefficient of friction (COF < 0.05) after continuous wear. The drag reduction rate of the coated surfaces reached 5%, showing a powerful lubrication performance. Furthermore, the DIP coatings presented an outstanding corrosion resistance, where the equivalent circuit impedances were 4–9 orders of magnitude higher than the control groups. This research showed a promising prospect of surface coating fabrication with DIP for marine devices to achieve the purpose of antifouling and drag reduction. [ABSTRACT FROM AUTHOR]

Purpose: Lymphoma has become a major threat to human health. Fortunately, the diagnosis and treatment of lymphoma have developed rapidly, and research progress has emerged in an endless stream, with new drugs emerging one after another. These results are constantly rewriting guidelines changing clinical practice, need to be popularized and applied more widely. Methods: This guideline has integrated consensuses reached by the Lymphoma Committee of China Anti-Cancer Association (CACA), based on China's practice, tracking previous results of the most advanced clinical researches, absorbing the latest clinical evidence, and referring to domestic and international lymphoma guidelines. Results: This holistic integrative guideline of lymphoma introduces the latest progress in the diagnosis and treatment of different subtypes of lymphoma, guide the clinical application of new drugs, standardized and precise management for lymphoma patients. Conclusions: CACA guidelines for holistic integrative management of lymphoma (version 2022) enhance standardization and precision of the management for lymphoma patients in China. [ABSTRACT FROM AUTHOR]

The incentive-based emergency demand response measure serves as an important regulatory tool during energy system operations. However, whether people will sacrifice comfort to respond to it during heatwave and what the effect on heat vulnerable populations will be are still unclear. A large-scale emergency demand response pilot involving 205,129 households was conducted in southwestern China during continuous extreme high temperatures in summer. We found that the incentive-based emergency demand response causes a statistically significant decline in electricity use with no additional financial burden on vulnerable groups. The electricity conservation potential of urban households was higher than that of rural households. Households with children did not respond to the emergency demand response, while the response of households with elderly individuals proved to be more positive. The repeated and frequent implementation of this policy did not result in an attenuation of the regulatory effect. This research can serve as a reference for countries with similar regulated power markets. Co-lead authors Wang, Zhang, Qiu, Lu and their colleagues model an incentive-based emergency demand response to counter heatwaves. The modelled responded leads to the peak load reduction of 7.32% for the covered households, and can achieve a 1.02% peak load reduction when reaching a wide audience with no additional financial burden on vulnerable groups. [ABSTRACT FROM AUTHOR]

Understanding the characteristics of cloud water resource (CWR) and precipitation efficiency of hydrometeors (PEh) is imperative for the application of CWR in Northwest China. The atmospheric precipitable water (PW) in all four seasons and clouds and PEh in summer were studied with ERA-5 and CloudSat data in this region. The results show that topography, especially in the Tibetan Plateau, exerts significant impacts on the precipitation and PW in summer, since large amounts of clouds are distributed along the mountain ranges. The study region is divided into four typical areas: the monsoon area in eastern Northwest China (NWE), the Qilian Mountains area (QM), the Tian-shan Mountains area (TM), and the Source of Three Rivers area (STR). Over the four areas, cloud top height (6.3 km) and cloud base height (3.3 km) over NWE are higher, and precipitating clouds are thicker (7 km) in the single-layer clouds. Liquid water content decreases with increasing altitude, while the ice water content first increases and then decreases. Liquid water path is higher over NWE (0.11 kg m−2) than over TM and STR (0.05 kg m−2), and the ice water path is mainly concentrated within the range of 0.025–0.055 kg m−2. The PEh values are distributed unevenly and affected evidently by the terrain. Although the PEh values in the four typical areas (0.3–0.6) are higher than those in other regions, the CWR is relatively abundant and has a higher exploitation potential. Therefore, it is well-founded to exploit CWR for alleviating water shortages in these areas of Northwest China in summer. [ABSTRACT FROM AUTHOR]

Background: Migraine is a disabling neurological disorder with the pathophysiology yet to be understood. The microstructural alteration in brain white matter (WM) has been suggested to be related to migraine in recent studies, but these evidence are observational essentially and cannot infer a causal relationship. The present study aims to reveal the causal relationship between migraine and microstructural WM using genetic data and Mendelian randomization (MR). Methods: We collected the Genome-wide association study (GWAS) summary statistics of migraine (48,975 cases / 550,381 controls) and 360 WM imaging-derived phenotypes (IDPs) (31,356 samples) that were used to measure microstructural WM. Based on instrumental variables (IVs) selected from the GWAS summary statistics, we conducted bidirectional two-sample MR analyses to infer bidirectional causal associations between migraine and microstructural WM. In forward MR analysis, we inferred the causal effect of microstructural WM on migraine by reporting the odds ratio (OR) that quantified the risk change of migraine for per 1 standard deviation (SD) increase of IDPs. In reverse MR analysis, we inferred the causal effect of migraine on microstructural WM by reporting the β value that represented SDs of changes in IDPs were caused by migraine. Results: Three WM IDPs showed significant causal associations (p < 3.29 × 10− 4, Bonferroni correction) with migraine and were proved to be reliable via sensitivity analysis. The mode of anisotropy (MO) of left inferior fronto-occipital fasciculus (OR = 1.76, p = 6.46 × 10− 5) and orientation dispersion index (OD) of right posterior thalamic radiation (OR = 0.78, p = 1.86 × 10− 4) exerted significant causal effects on migraine. Migraine exerted a significant causal effect on the OD of left superior cerebellar peduncle (β = − 0.09, p = 2.78 × 10− 4). Conclusions: Our findings provided genetic evidence for the causal relationships between migraine and microstructural WM, bringing new insights into brain structure for the development and experience of migraine. [ABSTRACT FROM AUTHOR]

Demand-side response (DSR) measures, which facilitate the management of system reliability and maintain system resource adequacy of power grids, are gaining prominence. Traditional optimization methods for residential electricity usage in peak-demand hours often lack flexibility and effectiveness in solving practical problems due to a large amount of data and a high degree of data uncertainty. Our study aims to obtain a high degree of responsiveness for numerous and highly dispersed residential customers by integrating data-driven and model-driven methods. In this study, we conducted large-scale DSR controlled trials, collected 15-min intervals of electricity consumption data, and matched the survey data. A dynamic time-warping clustering-based difference-in-difference method was proposed for empirical analysis. The results indicate that monetary incentives induced a statistically significant reduction in electricity usage during peak periods in summer by 18.6%, while the response effect was not significant in winter. The heterogeneity analysis suggests that the reduction was mainly contributed by the middle-income group and the elderly group. Our study provides a basis for policymakers to formulate tailored policies to optimize residents' electricity consumption during peak hours. [ABSTRACT FROM AUTHOR]

In order to investigate the overall cognition of blended learning, we made a questionnaire survey and interviews with students and teachers of 10 universities and colleges in Anhui Province. Based on this investigation, we design a Rain class blended learning model which fully utilizes the modern network technology and mobile terminals to closely link pre-class and after-class learning to classroom teaching by using Wechat terminal. In order to validate the application effect of the model, a quasi-experiment is conducted between two groups of students. We used SPSS 23.0 in recording and analyzing the data for inferential statistics, two independent samples T-test, variance analysis and descriptive statistical analysis. The difference was statistically significant with P < 0.05. The study found that students have higher interest and acceptance to blended learning, but miscellaneous online resources and excessive interference information have negative impacts on students' online learning participation behavior. The hypothesis about the influencing factors of blended learning has been verified empirically, that is, perceived ease of use, perceived usefulness, a learning atmosphere are important factors affecting learners' acceptance of blended learning. A teaching practice proved that the new learning model has achieved remarkable results in improving learning efficiency and quality of students in large classroom, cultivating students' learning initiative and stimulating their interest in learning. [ABSTRACT FROM AUTHOR]

We investigated recent ambient air quality and pollution in Zhangjiakou, China, from 2016 to 2020 by analyzing the interannual variability in the air quality index (AQI) variations, interannual and monthly tends of six conventional air quality indices, index-ratio characteristics, and correlations. We employed a Gray model for predicting air pollution control, providing insight into measures that may improve air quality during the coming 2022 Olympic Winter Games in Beijing and Zhangjiakou. The results showed that PM2.5 and PM10 (produced by industrial sources, coal consumption, vehicle emissions, and dust) increased in spring and decreased in summer; because the dust levels in Zhangjiakou are highest in spring, the PM2.5 and PM10 concentrations were higher in spring than in winter. SO2, NO2, and CO increased in winter and decreased in summer, SO2 and CO are primarily affected by heat, and NO2 is mainly affected by vehicle emissions. Monthly O3 concentrations increased in summer and decreased in winter, owing to meteorological conditions, such as solar radiation and air temperature. Pearson's correlation analysis suggested that PM10, PM2.5, NO2, CO, and SO2 are positively correlated and have similar emission patterns; while O3 is strongly negatively correlated with NO2, albeit less so in summer. According to backward trajectory and concentration-weighted trajectory (CWT) analysis, the February fine particulate pollution in Zhangjiakou was not only affected by local pollutants but also by pollutants from parts of Inner Mongolia, northern Shanxi, Mongolia, and other regions. We predict that the Zhangjiakou air quality during the 2022 Winter Olympics will be generally acceptable, but fine particulate matter concentrations may increase, presenting a human health risk. [ABSTRACT FROM AUTHOR]

BAHD superfamily acyltransferases play an important role in catalyzing and regulating secondary metabolism in plants. Despite this, there is relatively little information regarding the BAHD superfamily in barley. In this study, we identified 116 HvBAHD acyltransferases from the barley genome. Based on phylogenetic analysis and classification in model monocotyledonous and dicotyledonous plants, we divided the genes into eight groups, I-a, I-b, II, III-a, III-b, IV, V-a and V-b. The Clade IV genes, including Agmatine Coumarol Transferase (ACT) that is associated with resistance of plants to Gibberella fungi, were absent in Arabidopsis. Cis-regulatory element analysis of the HvBAHDs showed that the genes respond positively to GA3 treatment. In-silico expression and qPCR analysis showed the HvBAHD genes are expressed in a range of tissues and developmental stages, and highly enriched in the seedling stage, consistent with diverse roles. Single nucleotide polymorphism (SNP) scanning analysis revealed that the natural variation in the coding regions of the HvBAHDs is low and the sequences have been conserved during barley domestication. Our results reveal the complexity of the HvBAHDs and will help facilitate their analysis in further studies. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) organic–inorganic perovskite hybrid materials with enhanced stability have attracted wide attention in optoelectronic field in recent years. Efforts of exploring new 2D perovskites with various organic or inorganic components have been devoted to further improve their solar cell efficiencies. In this work, three structurally similar spacer cations of phenylethylammonium (PEA), 4-bromophenylethylammonium (BPEA) and 4-chlorophenylethylammonium (CPEA) are selected to prepare multilayered 2D perovskites. It is found that the introduction of halogen atoms in the organic cations positively influences the film quality, light absorption, charge transport, device performance and moisture stability of the resulting perovskites. The (BPEA)2(MA)4Pb5I16 and (CPEA)2(MA)4Pb5I16 perovskites exhibit efficiencies of 7.38% and 10.88%, respectively, which are much higher than that of (PEA)2(MA)4Pb5I16 (3.98%). Owning to the larger size and bigger electronegativity of halogen atom in spacer cations, the PCE of unsealed BPEA- and CPEA-based 2D perovskite devices maintains 73% and 63% of their original efficiency after 720 h exposure to 60% humid air, while the PEA-based 2D device decreases to 52% of its initial PCE. Our work demonstrates new insight to modify the quality and stability of 2D perovskite hybrids, highlighting the validity of molecule design of organic cations in improving the efficiency and stability of 2D perovskite solar cells. [ABSTRACT FROM AUTHOR]

Driven by the goal of “carbon neutrality” for achieving energy savings and carbon reductions, various industries are striving to continuously introduce green energy-saving products. This study contributes to providing pricing policies and product launch strategies for the green energy-saving product manufacturers, aiming at increasing their profitability when facing strategic consumers. We develop a two-period pricing model, which considers three pricing policies and three product launch strategies in the presence of green information sharing, and we then investigate the performance of two types of government subsidy programs. The basic results show that the manufacturers would share information and adopt price commitment or price matching with dual rollover launch, when both the information sharing cost and consumer strategic level are low. While sharing green information is always beneficial to manufacturers its impact on sales quantity depends on consumer strategic level and technology preference. The further finding suggests that the highest profits can be achieved by adopting both price commitment and price matching, whereas the largest sales quantity can only be obtained under dynamic pricing. To achieve the promotion goal under price commitment, we derive the optimal subsidies of the manufacturer and consumers, and the results indicate that subsidizing consumers can not only help to reach the maximum promotion but also eliminate the risk of market failure. This study is expected to provide insights of subsidy programs for policy makers to enable manufacturers to achieve the promotion goal of energy-saving product, and it also accelerates the development of sustainable supply chain management. [ABSTRACT FROM AUTHOR]