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Through the total cyclization of polyacrylonitrile, a bifunctional surface and abundant oxygen defects were constructed on the lithium-rich cathode, leading to an excellent electrochemical performance.

Anaerobic fermentation is effective for waste activated sludge (WAS) disposal to realize resource generation and pollutants reduction, and various pretreatments were commonly applied to improve the performance. This work mainly investigated the effects of typical WAS pretreatment approaches on the antibiotic resistance genes (ARGs, as emerging contaminants) removal during anaerobic fermentation processes and unveiled the underlying mechanisms. The results indicated that all the pretreatment strategies exhibited evident effects on the overall ARGs removal with the order of Fe

Ni,Co-MOFs have been synthetized by a simple hydrothermal method. Subsequently, Co,Ni/N-doped porous carbon have been prepared by pyrolysis method using the Ni,Co-MOFs as precursor. The results show that the samples present high degree of graphitization. The Co-1–Ni-0.5/NC possesses the largest BET surface area (94.73 m2/g) and pore volume (0.456 cm3/g). The Co-1–Ni-0.5/NC presents the smallest HER overpotential (179 mV) and the best electrocatalytic activity for HER. The Co-0.5–Ni-0.5/NC and Co-1–Ni-0.5/NC have the relatively low overpotential for OER, which are about 348 mV and 383 mV, respectively. The smallest Tafel slope value indicates that Co-1–Ni-0.5/NC presents the best electrocatalytic reactive kinetics. Excellent electrocatalytic performance may be attributed to the more active sites, the higher specific surface area and mesopores as well as the lower charge-transfer resistance. The excellent HER and OER of Co-1–Ni-0.5/NC make its potential to be used on overall water splitting.

Anionic charge compensation creates conditions for realizing high capacity and energy density of Li-ion batteries cathode materials. However, the issues of voltage hysteresis, capacity attenuation, and structure transformation caused by the labile anionic redox are still difficult to solve fundamentally. The superstructure formed by a Li-Mn ordered arrangement is the intrinsic reason to trigger the anionic charge compensation. In this work, manganese-based cathode materials with series of Li-Mn ordered superstructure types have been prepared by an ion exchange method, and superstructure control of the anionic redox behavior has been synthetically investigated. With the dispersion of a LiMn

Video question generation is a challenging task in visual information retrieval, which generates questions given a sequence of video frames. The existing methods mainly tackle the problem of single-turn video question generation, but single-turn conversation usually can’t meet the needs of video information acquisition. In this paper, we propose a new framework for single-turn VQG, which introduces attention mechanism to process inference of dialog history. And we introduce selection mechanism to choose from the candidate questions generated by each round of dialog history. In the framework, we leverage a recent video question answering model to predict the answer to the generated question and adopt the answer quality as rewards to fine-tune our model based on a reinforced learning mechanism. We also introduce a new task of multi-turn video question generation (M-VQG), which is generating multiple questions based on dialog history and video information to build conversation step by step. Our method achieves the state-of-the-art performance of the single-turn VQG task on two large-scale datasets, YouTube-Clips and TACoS-MultiLevel, and provides a baseline approach for M-VQG task.

7××× aluminum alloy is a metal with a high tendency to weld cracks. In the welding process, 7××× aluminum alloy wire was seldom used but low strength matching 4××× and 5××× aluminum alloy wire was used for joining, which had poor mechanical properties of welded joints. In this paper, a self-designed low copper 7A48 wire containing scandium was used as filler material for metal inert gas (MIG) welding of 4 mm thick A7N01-T4 aluminum alloy plates. The results show that the A7N01-T4 MIG welded joints were obtained with good seam formation and no crack formation. The equiaxed dendrites in the weld zone were found. The precipitated phases were primarily Mg-rich and Zn-rich, forming a typical 7××× aluminum alloy structure. In the fusion zone, fine equiaxial crystals were found, with a width of about 100 μm. In the heat-affected zone, grains growth occurred and the precipitated phase was dissolved or aggregated. The hardness of the WZ reached 81.7% of that of the base material and the softening of the WZ was not significant. The average tensile strength and elongation of the specimens were 364.9 MPa and 17.5%, respectively. The tensile fracture occurred in WZ and the fracture was dominated by microporous aggregation shear fractures with localized cleavage fractures occurring.

Ni-based surfacing coating was fabricated on the Cr12MoV die steel utilizing the ENiCrFe-2 alloy. The defect-free surfacing coating was obtained with a good metallurgical bonding between the coating and the substrate. The microstructure, element distribution, and micro-hardness were analyzed. Results showed that the microstructure was composed of planar crystals at the bottom of coating, and it consisted of columnar crystals at the middle region. There existed a diffusion layer with a width of about 100 μm at the ENiCrFe-2–Cr12MoV interface. Three regions were formed in the heat-affected zone with various microstructure morphologies. The average micro-hardness of coating was 275 HV0.5, which was more than that of Cr12MoV. Micro-hardness was dramatically increased (765 HV0.5) in the middle of the heat-affected zone. This was caused by the combined effect of grain refinement, solid solution strengthening, second-phase strengthening, and primary carbide strengthening. Moreover, the formation mechanism of middle heat-affected zone was discussed in this paper in detail.

Lithium-rich manganese-based cathode materials are expected to promote the commercialization of lithium-ion batteries to a new stage by virtue of their ultrahigh specific capacity and energy density advantages. However, they are still restricted by complex phase transitions and electrochemical performance degradation caused by labile anion charge compensation. A deep understanding of the electrochemical properties contained in their intrinsic structures and the key driving factors of structural deterioration during cycling are crucial to guide the preparation and optimization of lithium-rich materials. Considering recent progress, this review introduces the intrinsic properties of Li-rich manganese-based cathode materials from interatomic interactions to particle morphology at multiple scales in the spatial dimension. The charge compensation mechanism and energy band reorganization of the initial charge and discharge, the structural evolution during cycling and the electrochemical reaction kinetics of the materials are analyzed in the temporal dimension. Based on the relationship between structure and electrochemical performance, preparation methods and modification methods are introduced to guide and design cathode materials. Effective characterization methods for studying anion charge compensation behavior are also demonstrated. This review provides important guidance and suggestions for making full use of the high specific capacity in these materials derived from anion redox and the maintaining of its stability.

With high mortality and morbidity rates, lung cancer (LC) has become one of the major threats to human health. The treatment strategies for LC currently face issues, such as drug resistance and body tolerance. Traditional Chinese medicine (TCM) is characterized by novel pharmacological mechanisms, low toxicity, and limited side effects. TCM includes a substantial number of biologically active ingredients, several of which are effective monomeric agents against LC. An increasing number of researchers are focusing their efforts on the discovery of active anti-cancer ingredients in TCM.In this review, we summarized the anti-LC mechanisms of five types of TCM monomeric compounds. Our goal is to provide research ideas for the identification of new prospective medication candidates for the treatment of LC.We collected reports on the anti-LC effects of TCM monomers from web databases, including PubMed, Science Direct, Web of Science, and Europe PubMed Central. Among the keywords used were "lung cancer," "traditional Chinese medicine," "pharmacology," and their combinations thereof. Then, we systematically summarized the anti-LC efficacy and related mechanisms of TCM monomers.Based on the available literature, this paper reviewed the therapeutic effects and mechanisms of five types of TCM monomers on LC. The characteristics of TCM monomers include the capabilities to suppress the tumor cell cycle, inhibit proliferation, induce apoptosis, promote autophagy, inhibit tumor cell invasion and metastasis, and enhance efficacy or reduce drug resistance when combined with cytotoxic agents and other methods to arrest the progression of LC and prolong the survival of patients.TCM contains numerous flavonoids, alkaloids, terpenoids, polyphenols, and other active compounds that are effective against LC. Given their chemical structure and pharmacological properties, these monomers are suitable as candidate drugs for the treatment of LC.

Chronic intermittent hypoxia (CIH) and chronic sleep fragmentation (CSF) are two cardinal pathological features of obstructive sleep apnea (OSA). Dietary obesity is a crucial risk intermediator for OSA and metabolic disorders. Gut microbiota affect hepatic and adipose tissue morphology under conditions of CIH or CSF through downstream metabolites. However, the exact relationship is unclear. Herein, chow and high-fat diet (HFD)-fed mice were subjected to CIH or CSF for 10 weeks each and compared to normoxia (NM) or normal sleep (NS) controls. 16S rRNA amplicon sequencing, untargeted liquid chromatography-tandem mass spectrometry, and histological assessment of liver and adipose tissues were used to investigate the correlations between the microbiome, metabolome, and lipid metabolism under CIH or CSF condition. Our results demonstrated that CIH and CSF regulate the abundance of intestinal microbes (such as Akkermansia mucinphila, Clostridium spp., Lactococcus spp., and Bifidobacterium spp.) and functional metabolites, such as tryptophan, free fatty acids, branched amino acids, and bile acids, which influence adipose tissue and hepatic lipid metabolism, and the level of lipid deposition in tissues and peripheral blood. In conclusion, CIH and CSF adversely affect fecal microbiota composition and function, and host metabolism; these findings provide new insight into the independent and synergistic effects of CIH, CSF, and HFD on lipid disorders.

This paper studies how to automatically generate a natural language text that describes the facts in knowledge graph (KG). Considering the few-shot setting, we leverage the excellent capacities of pretrained language models (PLMs) in language understanding and generation. We make three major technical contributions, namely representation alignment for bridging the semantic gap between KG encodings and PLMs, relation-biased KG linearization for deriving better input representations, and multi-task learning for learning the correspondence between KG and text. Extensive experiments on three benchmark datasets have demonstrated the effectiveness of our model on KG-to-text generation task. In particular, our model outperforms all comparison methods on both fully-supervised and few-shot settings. Our code and datasets are available at https://github.com/RUCAIBox/Few-Shot-KG2Text., Accepted to ACL 2021 Findings

As a natural language generation task, it is challenging to generate informative and coherent review text. In order to enhance the informativeness of the generated text, existing solutions typically learn to copy entities or triples from knowledge graphs (KGs). However, they lack overall consideration to select and arrange the incorporated knowledge, which tends to cause text incoherence. To address the above issue, we focus on improving entity-centric coherence of the generated reviews by leveraging the semantic structure of KGs. In this paper, we propose a novel Coherence Enhanced Text Planning model (CETP) based on knowledge graphs (KGs) to improve both global and local coherence for review generation. The proposed model learns a two-level text plan for generating a document: (1) the document plan is modeled as a sequence of sentence plans in order, and (2) the sentence plan is modeled as an entity-based subgraph from KG. Local coherence can be naturally enforced by KG subgraphs through intra-sentence correlations between entities. For global coherence, we design a hierarchical self-attentive architecture with both subgraph- and node-level attention to enhance the correlations between subgraphs. To our knowledge, we are the first to utilize a KG-based text planning model to enhance text coherence for review generation. Extensive experiments on three datasets confirm the effectiveness of our model on improving the content coherence of generated texts., Comment: Accepted by SIGIR 2021 (Long Paper)

Personalized review generation (PRG) aims to automatically produce review text reflecting user preference, which is a challenging natural language generation task. Most of previous studies do not explicitly model factual description of products, tending to generate uninformative content. Moreover, they mainly focus on word-level generation, but cannot accurately reflect more abstractive user preference in multiple aspects. To address the above issues, we propose a novel knowledge-enhanced PRG model based on capsule graph neural network~(Caps-GNN). We first construct a heterogeneous knowledge graph (HKG) for utilizing rich item attributes. We adopt Caps-GNN to learn graph capsules for encoding underlying characteristics from the HKG. Our generation process contains two major steps, namely aspect sequence generation and sentence generation. First, based on graph capsules, we adaptively learn aspect capsules for inferring the aspect sequence. Then, conditioned on the inferred aspect label, we design a graph-based copy mechanism to generate sentences by incorporating related entities or words from HKG. To our knowledge, we are the first to utilize knowledge graph for the PRG task. The incorporated KG information is able to enhance user preference at both aspect and word levels. Extensive experiments on three real-world datasets have demonstrated the effectiveness of our model on the PRG task., Comment: Accepted by CIKM 2020 (Long Paper)

Fine-tuning pretrained model has achieved promising performance on standard NER benchmarks. Generally, these benchmarks are blessed with strong name regularity, high mention coverage and sufficient context diversity. Unfortunately, when scaling NER to open situations, these advantages may no longer exist. And therefore it raises a critical question of whether previous creditable approaches can still work well when facing these challenges. As there is no currently available dataset to investigate this problem, this paper proposes to conduct randomization test on standard benchmarks. Specifically, we erase name regularity, mention coverage and context diversity respectively from the benchmarks, in order to explore their impact on the generalization ability of models. To further verify our conclusions, we also construct a new open NER dataset that focuses on entity types with weaker name regularity and lower mention coverage to verify our conclusion. From both randomization test and empirical experiments, we draw the conclusions that 1) name regularity is critical for the models to generalize to unseen mentions; 2) high mention coverage may undermine the model generalization ability and 3) context patterns may not require enormous data to capture when using pretrained encoders., Accepted to EMNLP2020

Rapid agricultural land expansion and urbanization have accelerated land use and land cover changes (LUCC) in the Northern Tianshan Mountain Economic Zone and have significantly impacted on the ecosystem services (ESs). However, the spatiotemporal variations of ecosystem service value (ESV) to LUCC are not well understood. Based on the land use and land cover (LULC) data from 1980 to 2019, we used a CA-Markov model to predict LUCC in 2020 and 2030, assess the spatial-temporal changes of ESV and LULC during 1980–2030, and explore the elastic response of ESV to LUCC. We found that cropland and built-up land expanded rapidly by 34.38% and 196.66%, respectively between 1980 and 2030, while grassland and unutilized land decreased significantly by 11.45% and 10.26%, respectively. The ESV of water body, cropland, grassland and forestland accounts for more than 90% of the total ESV. Our research shows that the ESV of cropland increased 32 million yuan from 1980 to 2030, mainly due to the expansion of cropland area. However, the loss caused by the reduction of grassland area was 45 million yuan. Water conservation, waste treatment, soil formation and retention, and biodiversity conservation are the primary ecosystem service function, accounting for 71.82% of the total ESV. Despite notable increases in the ESV from 1980 to 2010, grassland degradation still remains a main ecological and environmental issue from 2010 to 2030. The results suggest that effective land use policies should be developed to control the expansion of croplands and protect water body, grassland and forestland to maintain more sustainable ESs.

Phosphogypsum (PG) is an acid by-product from the production phosphate fertilizers that is produced in large amounts all over the world. However, it is challenging to reuse this waste due to the quantities of various impurities in PG and technical restrictions, resulting in PG accumulation, which threatens adjacent environments. To reduce PG storage and safely utilize PG, the aim of our study was to define the leaching characteristics of the impurities present in PG under different conditions. We found that (1) different leaching experiments showed different leachate profiles (including pH and electrical conductivity values of leachate), which indicated that the liquid/solid (L/S) ratio, temperature, oscillation strength, particle size, and pH have remarkable effects on the concentration of leached impurities; (2) all leachate (i.e. soluble P, fluoride, Zn, Pb, As, and Hg) extraction concentrations were significantly more sensitive to the effect of the L/S ratio and pH than the effect of the other conditions; and (3) the leaching concentration was strongly influenced by pH, and a strong correlation among soluble P, F, As, and Hg concentrations in the leachate was demonstrated by a correlation analysis. In the present study, we revealed a systematic leaching mechanism of potential toxic elements in PG and have provided guidance and a reference for PG resource comprehensive utilization and surrounding environment treatment. Supplementary material: Chemical compositions of the phosphogypsum and pairwise Wilcoxon test results are available at https://doi.org/10.6084/m9.figshare.c.5088187

Integrated energy system is efficient and flexible in distributed energy supply, but the coupling of energy flows and the inaccuracy of prediction bring challenges to its economic operation. Peak shaving and demand management have become a necessary part of its operation method. In this paper, a cooperative dispatch method is proposed to optimize daily operations that consider the coupling characteristics of multi-energy flow in integrated energy systems. In addition, given the limitations of long-term and short-term prediction, a dynamic correction operation mode is proposed to improve the accuracy of the dispatch plan. In the case study, domestic hot water systems and charging piles are taken as dispatchable electricity demand, and indoor temperature is dispatchable cooling and heating demands. Electric energy storage is taken as the peak-shaving tool for electricity, and air conditioning circulation water is taken for cooling and heating. Based on this, daily operations over five winter days and five summer days are compared. The results show that, after applying this cooperative dispatch method, the energy supply costs are reduced by 10.82%, and carbon emissions are reduced by 9.71%. Meanwhile, the average energy efficiency is increased by 6.42%, and the average exergy loss rate is reduced by 5.46%.

s Phosphogypsum (PG) is an acid by-product generated during the breakdown of phosphate ore in the presence of sulfuric acid and has been used as a soil amendment, i.e., fertilizer, in most parts of the world. PG application can improve some soil properties and increase crop yields. However, PG application in agriculture threatens agroecological systems and food safety because of the high amounts of environmentally and biologically available potentially toxic elements (PTEs) in PG. Recently, biochar has been found to strongly immobilize and adsorb PTEs as well as suppress PTE phytoavailability. Hence, in this context, bench-scale batch and column experiments were performed to test the availability of PTEs in PG under different pyrolysis temperatures and different percentages of rice husk biochar (RHB). Subsequently, pot experiments were performed to test the effect of RHB addition on the PTE concentrations in crops when PG was added to different types of soil, and the effect of the RHB and PG combination on crop yield was determined. The batch and column experimental results showed that the pyrolysis temperature and biochar dose significantly reduced the PTE concentrations in PG because the biochar physicochemical properties, components, and types of functional groups, which were analysed by XRF, XRD and FTIR, were mainly controlled by temperature. The preparation temperature (600 °C) and applied dose (60%, w/w) of RHB were optimized through a mixed-effect model. Furthermore, the mechanism underlying P, F and heavy metals in PG leachates adsorbed onto biochar was determined by XPS analysis, which showed that surface ions and different functional groups played a dominant role through precipitation and complexation. Compared to the control, application of the combination to loam soil or sand significantly increased (56.04% and 604.66%, respectively) crop yield. The combination significantly decreased PTE concentrations (As, F, Cd, and Pb by 39, 41, 75, and 86%, respectively, in water spinach and by 100%, 64%, 75%, and 88%, respectively, in asparagus lettuce) in edible parts of crops compared to PG treatment only. Moreover, RHB + PG reduced pollution to the surrounding environment by decreasing the PTE contents in the leachate. These findings suggest that the improved effectiveness of the combination was greater in sand because of its weak buffering ability, and the RHB and PG combination can be a useful and safe soil amendment to provide good guidance for waste management and comprehensive utilization of waste.