Remaining Useful Life (RUL) prediction of drilling pumps, pivotal components in fossil energy production, is essential for efficient maintenance and safe operation of such facilities. This paper ...introduces a deep feature learning method that combines a Convolutional Neural Network (CNN)-Convolutional Block Attention Module (CBAM) and a Transformer network into a parallel channel method to predict the RUL of drilling pumps. Specifically, two parallel channels independently extract time-frequency domain and time-domain features from strain signals and then proceed with degradation estimation through feature learning. The deep features derived independently from the two channels are subsequently amalgamated to predict the RUL of the drilling pump. The proposed method is validated by the operational data from four operating drilling pumps. The comparative analysis confirms the higher accuracy of the proposed method over several existing state-of-the-art approaches. Overall, the proposed method supports the safe and cost-saving-oriented operation and maintenance of drilling pumps.
•Time and time-frequency domain features are incorporated as inputs of the model.•Feature weights are adaptively assigned by the CBAM and multi-head attention mechanisms.•A parallel feature extraction structure is created for model generalization and overfitting risk reduction.
Perovskite solar cells (PSCs) may offer huge potential in photovoltaic conversion, yet their practical applications face one major obstacle: their low stability, or quick degradation of their initial ...efficiencies. Here, a new design scheme is presented to enhance the PSC stability by using low‐temperature hydrothermally grown hierarchical nano‐SnO2 electron transport layers (ETLs). The ETL contains a thin compact SnO2 layer underneath a mesoporous layer of SnO2 nanosheets. The mesoporous layer plays multiple roles of enhancing photon collection, preventing moisture penetration and improving the long‐term stability. Through such simple approaches, PSCs with power conversion efficiencies of ≈13% can be readily obtained, with the highest efficiency to be 16.17%. A prototypical PSC preserves 90% of its initial efficiency even after storage in air at room temperature for 130 d without encapsulation. This study demonstrates that hierarchical SnO2 is a potential ETL for fabricating low‐cost and efficient PSCs with long‐term stability.
Low‐temperature hydrothermally grown hierarchical SnO2
, a mesoporous layer of nanosheet arrays on a compact nanoparticle layer, is used as the electron transporting layer to enhance the long‐term stability of perovskite solar cells. A mesoporous device preserves 90% of its initial efficiency, even after storage in air for 130 d without encapsulation.
Six new C-20 and one new C-19 quassinoids, named perforalactones F-L (1–7), were isolated from twigs of Harrisonia perforata. Spectroscopic and X-ray crystallographic experiments were conducted to ...identify their structures. Through oxidative degradation of perforalactone B to perforaqussin A, the biogenetic process from C-25 quassinoid to C-20 via Baeyer–Villiger oxidation was proposed. Furthermore, the study evaluated the anti-Parkinson’s disease potential of these C-20 quassinoids for the first time on 6-OHDA-induced PC12 cells and a Drosophila Parkinson’s disease model of PINK1B9. Perforalactones G and I (2 and 4) showed a 10–15% increase in cell viability of the model cells at 50 μM, while compounds 2 and 4 (100 μM) significantly improved the climbing ability of PINK1B9 flies and increased the dopamine level in the brains and ATP content in the thoraces of the flies.
The design of heterojunction with superior performance of light absorption and appropriate conduction band and valence band potentials is a promising approach for the applications in efficient ...environmental remediation and the solar energy storage. In recent years, many studies have been devoted to the applications of graphitic carbon nitride (g-C3N4)-based heterojunction photoactive nanomaterials under visible light irradiation due to its excellent physical, optical, and electrical properties, which inspired us to compile this review. Although many reviews demonstrated about the syntheses and applications of g-C3N4 composites, a targeted review on the systematic application and photocatalytic mechanisms of g-C3N4-based heterojunction, in which components are in intimate linkage with each other rather than a physical mixture, is still absent. In this review, the applications of g-C3N4-based heterojunction photoactive nanomaterials in environmental remediation and solar energy storage, such as photocatalytic treatment of persistent organic pollutants, heavy-metal-ion redox, oxidative decomposition of pathogens, water splitting for H2 evolution, and CO2 reduction, are systematically discussed. In addition, some emerging applications, such as solar cells and biosensors, are also introduced. Meanwhile, a comprehensive assessment on the basis of first-principles calculations and the thermodynamics and kinetics of surface catalytic reaction for the electronic structure and photocatalytic properties of g-C3N4-based heterojunction are valued by this review. In the end, a brief summary and perspectives in designing practical heterojunction photoactive nanomaterials also showed the bright future of g-C3N4-based heterojunction. Altogether, this review systematically complements the information that previous reviews have frequently ignored and points out the future development trends of g-C3N4-based heterojunction, which expected to provide important references and right directions for the development and practical applications of g-C3N4-based heterojunction photoactive nanomaterials.
L., commonly referred to as dry, green, or field pea, is one of the most common legumes that is popular and economically important. Due to its richness in a variety of nutritional and bioactive ...ingredients, the consumption of pea has been suggested to be associated with a wide range of health benefits, and there has been increasing focus on its potential as a functional food. However, there have been limited literature reviews concerning the bioactive compounds, health-promoting effects, and potential applications of pea up to now. This review, therefore, summarizes the literature from the last ten years regarding the chemical composition, physicochemical properties, processing, health benefits, and potential applications of pea. Whole peas are rich in macronutrients, including proteins, starches, dietary fiber, and non-starch polysaccharides. In addition, polyphenols, especially flavonoids and phenolic acids, are important bioactive ingredients that are mainly distributed in the pea coats. Anti-nutritional factors, such as phytic acid, lectin, and trypsin inhibitors, may hinder nutrient absorption. Whole pea seeds can be processed by different techniques such as drying, milling, soaking, and cooking to improve their functional properties. In addition, physicochemical and functional properties of pea starches and pea proteins can be improved by chemical, physical, enzymatic, and combined modification methods. Owing to the multiple bioactive ingredients in peas, the pea and its products exhibit various health benefits, such as antioxidant, anti-inflammatory, antimicrobial, anti-renal fibrosis, and regulation of metabolic syndrome effects. Peas have been processed into various products such as pea beverages, germinated pea products, pea flour-incorporated products, pea-based meat alternatives, and encapsulation and packing materials. Furthermore, recommendations are also provided on how to better utilize peas to promote their development as a sustainable and functional grain. Pea and its components can be further developed into more valuable and nutritious products.
Adsorption of tetracycline antibiotics from aqueous solutions by a multi-walled carbon nanotube (MWCNT) loaded iron metal-organic framework (MIL-53(Fe)) composite was studied. The adsorbent was ...characterized by environmental scanning electron microscope, energy dispersive X-ray spectroscopy, brunauer-emmett-teller, thermogravimetric analysis, X-ray diffraction, fourier transform infrared spectrum, and X-ray photoelectron spectrum. The adsorption kinetics of tetracycline hydrochloride (TCN), oxytetracycline hydrochloride (OTC), and chlortetracycline hydrochloride (CTC) were all well fitted to the pseudo-second-order equation as well as the adsorption isotherms could be well delineated via Langmuir equations. The main influencing factors such as pH and ionic strength were studied in detail. At initial pH of 7.0, maximum adsorption capacity of TCN, OTC and CTC on MWCNT/MIL-53(Fe) was 364.37, 325.59, 180.68 mg·g−1 at 25 °C, which was 1.25, 8.28 and 3.34 times than that of single MWCNT, respectively. The adsorption capacity of TCS for this adsorbent was in the order: TCN > OTC > CTC, which was determined by the adsorbate molecule magnitude. In addition, π-π adsorbate-adsorbent interactions played an important role during the adsorption process. The excellent reusability and great water stability indicated the potential application of this novel composite in the removal of TCS from aqueous solutions.
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•Multi-walled carbon nanotube modified MIL-53(Fe) was used to remove antibiotic tetracycline for the first time.•MWCNT/MIL-53(Fe) showed the highest adsorption capacity for TCN, OTC and CTC, respectively.•π-π interactions were possible mechanism for adsorptive removal of TCN, OTC and CTC.•MWCNT/MIL-53(Fe) with great water stability was suggested as a reusable and efficient adsorbent.
Congestion detection is an important aspect of vehicular management. However, most of the existing algorithms are insufficient for real applications. Traditional features are not discriminative which ...results in rather poor performance under complex scenarios. The deep features can better represent high-level information, but the training of deep network for regression is difficult. To promote the congestion detection, a robust hierarchical deep learning is proposed for the task. In this method, a deep network is designed for hierarchical semantic feature extraction. Different from traditional deep regression networks, which usually directly utilize mean squared error as loss function, a robust metric learning is employed to effectively train the network. Based on this, multiple networks are combined together to further improve the generalization ability. Extensive experiments are conducted and the proposed model is confirmed to be effective.
In this paper, we consider a problem of estimating a large loss probability of financial derivatives portfolio, which are commonly modeled as nested expectations. However, the cost of nested ...simulation may be too expensive and thus multilevel Monte Carlo (MLMC) method is recently used to reduce the nested simulation complexity. When using antithetic MLMC to solve the indicator function, we get the complexity of O(e-5^2). To decrease the computational burden, we use a Fourier transform method to modify the form of indicator function. The new estimator is sufficiently smooth and enables the antithetic MLMC method to achieve a better complexity. In addtion, we combine quasi-Monte Carlo (QMC) with MLMC to reduce the variance of inner estimator. Numerical results show that using the Fourier transform method in both MLMC and MLQMC can attain the optimal complexity О (e-2).
•Pig manure derived biochars (PBCs) have the best adsorption capacity for Cd2+.•The contribution of involved Cd2+ removal mechanism varied with feedstock.•Cd2+-π interaction was the predominant ...mechanism for Cd2+ removal on biochars.•The ash content play an important role in the removal of heavy metal by PBCs.
The objective of this study was to investigate the adsorption behavior and the relative distribution of Cd2+ sorption mechanisms on biochars by different feedstock. Bamboo biochars (BBCs), corn straw biochars (CBCs) and pig manure biochars (PBCs) were prepared at 300–700 °C. Adsorption results showed PBCs have the best adsorption capacity for Cd2+, the extra adsorption capacity of PBCs mainly attributed to the precipitation or cation exchange, which played an important role in the removal of Cd2+ by PBCs. The contribution of involved Cd2+ removal mechanism varied with feedstock due to the different components and oxygen-containing functional groups. Cd2+-π interaction was the predominant mechanism for Cd2+ removal on biochars and the contribution proportion significantly decreased from 82.17% to 61.83% as the ash content increased from 9.40% to 58.08%. Results from this study may suggest that the application of PBC is a feasible strategy for removing metal contaminants from aqueous solutions.
Background/Aims: Sepsis is a severe and complicated syndrome that is characterized by dysregulation of host inflammatory responses and organ failure. Cystathionine-γ-lyase (CSE)/ hydrogen sulfide ...(H2S) has potential anti-inflammatory activities in a variety of inflammatory diseases. NADPH oxidase 4 (Nox4), a member of the NADPH oxidases, is the major source of reactive oxygen species (ROS) and its expression is increased in sepsis, but its function in CSE-mediated anti-inflammatory activities remains unknown. Methods: Macrophages were either transfected with CSE, Nox4 siRNA or transduced with lentiviral vector encoding CSE or Nox4, and then stimulated with lipopolysaccharide (LPS). The expression of inflammatory mediators and signaling pathway activation were measured by quantitative PCR (qPCR), ELISA, and immunoblotting. LPS-induced shock severity in WT, Nox4 knockdown and CSE knockout (CSE-/-) mice was assessed. Results: Here we showed that CSE and Nox4 were upregulated in macrophage and mouse in response to LPS. After LPS stimulation, the inflammatory responses were significantly ameliorated by lentiviral Nox4 shRNA knockdown, but were exacerbated by lentiviral overexpressing Nox4. Furthermore, Nox4 mediated inflammation through PI3K/Akt and p-p38 mitogen-activated protein kinase signal pathway. Notably, CSE knockout served to amplify the inflammatory cascade by increasing Nox4-ROS signaling activation in septic mice and macrophage. Similarly, the enhanced production of inflammatory mediators by macrophages was reduced by CSE overexpression. Conclusion: Thus, we demonstrated that CSE/H2S attenuated LPS-induced sepsis against oxidative stress and inflammation damage probably largely through mediated Nox4 pathway.
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