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Abstract: The evaluation of the risk of underground gas pipeline can provide effective decision support aid. It is crucial to the establishment of a comprehensive safety evaluation and management system for the urban underground gas pipeline. This paper presents a method of GIS-based fuzzy comprehensive evaluation on underground gas pipeline risk and elaborates the flow of fuzzy risk evaluation in detail. Meanwhile, a fuzzy comprehensive evaluation model is built herein by analyzing the pipeline risk factor weight by means of analytic hierarchy process according to the fuzzy evaluation matrix for relative single-factor membership. Finally, a fuzzy comprehensive evaluation with test data is made on the failure to research the regional gas pipeline issue, the relative risk value of the pipelines in the area is calculated and visualization is made in 3DGIS scene. [Copyright &y& Elsevier]

Torreya grandis has been an economic forest crop in China for a long history. The side products of T. grandis oil would cause environmental problems and financial burden. Hydrolyzation of T. grandis meal protein can better utilize T. grandis and reduce its side products. The current study systematically investigated the enzymolysis of T. grandis : Alkaline proteinase was screened from five enzymes; when degree of hydrolysis at 12%; the hydrolysates exhibited the best antioxidant capacity; enzymatic model was fitted as DH = 4.55ln[1+(4.29E0/S0-0.07) t)] (DH: degree of hydrolysis); the investigations of amino acid compositions of T. grandis protein and its hydrolysates showed that amino acids supplementary would be necessary to optimize better bioactivity; the results of antioxidant capacity varied due to different dominant factors (i.e., molecular weight, amino acid compositions, peptide structures, etc.); the discrepancy of predict and actual solubilities could be caused by influences of peptide structures; foaming capacity was uncorrelated with molecular weight; low molecular weight of T. grandis protein hydrolysates presented poor foaming stability; emulsifying stability of T. grandis protein hydrolysates was affected more by the hydrophobic amino acid composition than molecular weight. This comprehensive study and investigated processes are useful that can be utilized to different natural product developments (including T. grandis). •The enzymolysis of Torreya grandis was systematically investigated. •The suitable enzyme (Alkaline proteinase) was screened from five, the optimal degree of hydrolysis (12%) was selected. • The enzymatic model was fitted (DH = 4.55ln[1+(4.29E0/S0-0.07) t)]). •Peptide fractions of T. grandis Meal were obtained (>10 kDa T1, 3–10 kDa T2, <3 kDa T3). The amino acids compositions of T. grandis Meal and its hydrolysates were studied. •The antioxidant capacity of T. grandis Meal hydrolysates were evaluated. The discrepancy of their results was analyzed. •Functional properties of T. grandis Meal hydrolysates were determined. [ABSTRACT FROM AUTHOR]

Abstract: ZnO was used to the surface modification of LiMn2O4 by sol–gel method to improve the elevated temperature performance of LiMn2O4. The electrochemical performance of the uncoated and ZnO-coated LiMn2O4 were investigated under a current rate of C/2 at 55°C, between 3.4V and 4.3V. While the uncoated LiMn2O4 delivered an average capacity loss of 0.81% per cycle in 50 cycles, the 1wt.%, 2wt.% and 5wt.% ZnO-coated LiMn2O4 only showed the average capacity loss of 0.54%, 0.19% and 0.14% per cycle, respectively. XRD results of the cathode materials after 50 cycles at 55°C revealed that ZnO coating could effectively suppress the dissolving of LiMn2O4 into electrolyte and resulted in a better stability. [Copyright &y& Elsevier]

Abstract: Lithium niobate crystal was successfully synthesized via hydrothermal synthesis method using LiOH·H2O or LiNO3 and Nb2O5 as starting materials in water or ammonia solution. X-ray diffraction (XRD), Fourier-transform infrared (FT-IR) spectra and Scanning electron microscopy (SEM) were used to characterize the as-prepared samples. The synthesis conditions such as crystallization temperature and time as well as ammonia concentration (when using LiNO3 as Li source) were investigated. The results demonstrate that the crystallization and purity of the as-prepared samples were increased with the increase of time when temperature was at 260 °C. When using LiNO3 as Li source a basic solution was necessary to synthesize LiNbO3. In the present work ammonia solution was used instead of water to obtain alkalescence solvent. XRD results revealed that the as-prepared samples had a hexagonal structure. FT-IR results displayed that the LiNbO3 phase could be completely formed and no secondary phase was found under proper conditions. SEM picture showed that the morphology of the sample was more perfect and bigger with increasing reaction time. [Copyright &y& Elsevier]

LiFe5O8 is regarded as a promising material, which is used as anode for lithium‐ion batteries on account of its lower cost and higher theoretical capacity. However, its practical applications are hindered by the low electron transfer rate, poor cycling performance, and huge magnification of lattice volume. In this work, a LiFe5O8/carbon nanotubes (CNTs) composite anode is designed to realize the ideal anode for low‐cost lithium‐ion batteries, showing broad commercial application prospects. It is found that the three‐dimensional conductive network of CNTs is used to accelerate electron transfer rate within the LiFe5O8 particles, thereby significantly reducing the reversible reaction barrier (Fe/Fe3O4). In addition, it can also alleviate the volume change of electrode, which maintains a stable Li+ insertion/extraction behavior during long‐term cycles. As a consequence, there is still a high capacity (427.3 mAh g−1) of the LiFe5O8/CNTs 3% anode reserved after 50 cycles at 0.5 C whereas the bare LiFe5O8 anode only delivers a low capacity of 220.6 mAh g−1 along with a poor cycling stability. This work highlights the outstanding contribution of electronic conductivity toward the electrochemical performance of LiFe5O8 anode and provides a low‐cost and commercially applicable composite anode for developing lower cost lithium‐ion batteries. [ABSTRACT FROM AUTHOR]

Mildew infestation is a significant cause of loss during grain storage. The growth and metabolism of mildew leads to changes in gas composition and temperature within granaries. Recent advances in sensor technology and machine learning enable the prediction of grain mildew during storage. Current research primarily focuses on predicting mildew occurrence or grading using simple machine learning methods, without in-depth exploration of the time series characteristics of mildew process data. A monitoring device was designed and developed to capture high-quality microenvironment parameters and image data during a simulated mildew process experiment. Using the "Yongyou 15" rice varieties from Zhejiang Province, five simulation experiments were conducted under varying temperature and humidity conditions between January and May 2023. Mildew grades were defined through manual analysis to construct a multimodal dataset for the rice mildew process. This study proposes a combined model (CNN–LSTM–A) that integrates convolutional neural networks (CNN), long short-term memory (LSTM) networks, and attention mechanisms to predict the mildew grade of stored rice. The proposed model was compared with LSTM, CNN–LSTM, and LSTM–Attention models. The results indicate that the proposed model outperforms the others, achieving a prediction accuracy of 98%. The model demonstrates superior accuracy and more stable performance. The generalization performance of the prediction model was evaluated using four experimental datasets with varying storage temperature and humidity conditions. The results show that the model achieves optimal prediction stability when the training set contains similar storage temperatures, with prediction accuracy exceeding 99.8%. This indicates that the model can effectively predict the mildew grades in rice under varying environmental conditions, demonstrating significant potential for grain mildew prediction and early warning systems. [ABSTRACT FROM AUTHOR]

The applications of lithium (Li)–sulfur (S) batteries are simultaneously hampered by the unlimited dendritic Li growth and the sluggish redox kinetics of polysulfides (LiPSs). In this work, an electronic state‐modulated Ni4N/Zn3N2 heterogeneous nanosheet arrays is painstakingly fabricated on the surface of carbon cloth (CC@Ni4N/Zn3N2) as an efficient bi‐service host to promote uniform Li deposition and boost efficient LiPSs catalysis. It is found that the electronic structure of Ni4N/Zn3N2 heterostructure is modulated to realize a rational transition metal d‐band center, and its built‐in electric field (BIEF) within the heterointerfaces facilitates the interfacial charge transfer, resulting in low Li deposition/migration energy barrier and efficient LiPSs adsorption/catalytic conversion kinetics. As a result, the as‐prepared CC@Ni4N/Zn3N2‐Li anode can enable the Li||Li symmetrical cells to possess a long‐term lifespan over 500 h even at 10 mA cm−2/20 mAh cm−2, and the as‐assembled LiNi0.8Co0.1Mn0.1O2||CC@Ni4N/Zn3N2‐Li full cell also shows an excellent cycling performance (95.8% capacity retention after 100 cycles). When used for both S and Li loading, the as‐assembled CC@Ni4N/Zn3N2‐S||CC@Ni4N/Zn3N2‐Li full cell exhibits an outstanding cycling stability (744 mAh g−1 after 1000 cycles at 2C). This work highlights the great potential of heterostructures for fabricating ideal bi‐serve hosts for both Li and S electrodes. [ABSTRACT FROM AUTHOR]

With regard to deep mining in metal mines, an investigation into the failure mode of deep fractured rock masses and their corresponding acoustic emission signal characteristics is conducted via uniaxial compression tests. Subsequently, a fractal damage renormalization group mechanical model is developed to explain the behavior of those fractured rock masses. Employing the bonded block model (BBM) numerical simulation method, fracture process in synthetic rock samples is analyzed, thereby validating the efficacy of the mechanical model. The numerical simulations highlight the critical role of fractures expansion in underlying the deterioration of rock mass strength. As the peak load decreases, the fracture fractal dimension increases, leading to a significant 14.2% reduction in compressive strength accompanied by an approximate 8.7% rise in average fracture fractal dimension. A comparative analysis of tetrahedral and voronoi block synthetic rock samples reveals the tetrahedral block samples exhibit a superior ability to depict the fracture behavior of fractured rock masses. Specifically, they offer a more accurate simulation of acoustic emission characteristics and failure modes. Furthermore, variations in the fracture fractal dimension with respect to the hole defect's position are observed, with the maximum value occurring along the vertical axis of the hole defect. This observation underscores the potential utility of visually monitoring deep rock fracture dynamics as an effective mean for quantitatively evaluating fracture damage and strength degradation in deep rock formations. [ABSTRACT FROM AUTHOR]

Describing the basic properties of road network systems, such as their robustness, vulnerability, and reliability, has been a very important research topic in the field of urban transportation. Current research mainly uses several statistical indicators of complex networks to analyze the road network systems. However, these methods are essentially node-based. These node-based methods pay more attention to the number of connections between nodes, and lack of consideration for interactions, leading to the well-known node paradox problem, and their ability of characterizing the local and intrinsic properties of a network is weak. From the perspective of network intrinsic geometry, we propose a method for measuring road network vulnerability using a discrete Ricci curvature, which can identify the key sections of a road network and indicate its fragile elements. The results show that our method performs better than complex network statistics on measuring the vulnerability of a road network. Additionally, it can characterize the evolution of the road network vulnerability among different periods of time in the same city through our method. Finally, we compare our method with the previous method of centrality and show the different between them. This research provides a new perspective on a geometry to analyze the vulnerability of a road network and describes the inherent nature of the vulnerability of a road system from a new perspective. It also contributes to enriching the analytical methods of complex road networks. • The Ricci curvature model provides a geometric view to measure road network vulnerability. • Negative curvatures indicate weaker links in the road network. • The Ricci curvature model is better than the betweenness centrality model on attack experiment. [ABSTRACT FROM AUTHOR]

BACKGROUND: Okara cellulose is a highly abundant, green, sustainable, and biodegradable polymer with many potential industrial applications. In this study, we fabricated composite hydrogels with okara cellulose nanofibers (CNFs) and chitosan (CH) by hydrating, sonicating, and heating them at 100 °C for 30 min, and then induced their assembly by cooling. The effects of okara CNF (with and without 2,2,6,6‐tetramethylpiperidinyloxy (TEMPO) oxidation) and CH concentration on the structure and properties of the hydrogels was examined, including their microstructure, surface properties, rheological properties, and thermal stability. RESULTS: Our results indicate that there was an electrostatic attraction between the anionic okara CNF and cationic CH, which facilitated hydrogel formation. The surface, textural, rheological, and thermal stability properties were better for the composite hydrogels than for the single CH ones, as well as for the CNF that had undergone TEMPO oxidation. For the TC‐CH hydrogels, the contact angle was 39.5°, the interfacial tension was 69.1 mN m−1, and the surface tension was 1.44 mN m−1. CONCLUSION: In this study, the novel hydrogels developed may be useful as a soft material in a range of applications in foods, supplements, health care products, cosmetics, and drugs. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Orthorhombic LiMnO 2 nanorods were prepared via a simple and economical in-situ carbothermal reduction method using nanorod-like MnO 2 as both template and manganese precursor. The obtained product showed high purity and excellent electrochemical performance. When used as a cathode material, it exhibited 165.3 mAh g −1 capacity with low capacity loss at 0.1 C. After 40 cycles, only 7.4% of discharge capacity was lost in the cycling process. Moreover, the maximum discharge capacities of 227.5 and 95.3 mAh g −1 could be delivered at low and high rates of 0.05 and 1.0 C, respectively. [ABSTRACT FROM AUTHOR]