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Factor analyses on the thermal stability of bio-oil formaldehyde resin by TG and Py-GC/MS methods

BIOMASS CONVErSION ANd BIOrEFINErY 2025年第5期15卷 7733-7749页

作者： Wang, Yifei Wang, Ze Wang, Jun Li, Songgeng Chinese Acad Sci State Key Lab Multiphase Complex Syst Inst Proc Engn Beijing 100190 Peoples R China Univ Chinese Acad Sci Sino Danish Coll Sino Danish Ctr Educ & Res Beijing 100190 Peoples R China Sinochem Fertilizer Corp Ltd Beijing 100031 Peoples R China

Phenol formaldehyde resin (PFr) has been widely used in many fields, including adhesion, refractory, coating, mold, and foam plastics. However, with the depletion of fossil fuels and more concerns on carbon neutral in recent years, the application of bio-oil to prepare bio-oil formaldehyde resin (BFr) for replacing phenol with bio-oil is arousing great interest, which is beneficial for reducing the carbon emission and the production cost. However, the thermal stability of BFr is far from satisfactory. More flammable and toxic volatile substances will be released from BFr than from PFr, which strongly poses safety and healthy risks to the fabricating workers and the users of the resin. In this work, the thermal stability of BFr is investigated by TG and Py-GC/MS methods, for better understanding the reasons behind the low thermal stability of BFr and for improving the thermal stability of the resin. The content of phenols and the presence of some non-phenolic compounds in bio-oil, as well as the catalyst dosage of NaOH, are studied. It is found that acetic acid has a strong inhibiting role to the reaction. The addition of NaOH can improve the thermal stability, but a large amount of NaOH may reversely promote the release of volatile matters. The separation of acetic acid before polymerization is a better choice than the addition of more NaOH. The reaction is found more complex beyond the factors discussed, so more parameters such as the curing conditions are necessary for further investigations in future work.

关键词： Factor analysis Preparation Bio-oil Bio-oil formaldehyde resin Fractionation

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Effect of complex-grain-size curves on shear modulus degradation of calcareous sand

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MArINE GEOrESOUrCES & GEOTECHNOLOGY 2025年第4期43卷 665-675页

作者： Wen, Liwei Huang, Zhanhu Fu, Qiang Xie, Wangfei Huang, Zhihong Wu, Yang Guangzhou Univ Sch Civil Engn Guangzhou Guangdong Peoples R China

The dynamic shear modulus G and its degradation tendency G/Gmax are essential parameters for characterizing the dynamic properties of soil. Coastal facilities constructed on calcareous sand foundations are subjected to multiple types of cyclic loadings. To investigate the effects of the uniformity coefficient Cu, effective confining pressure sigma 0 ', relative density dr, and median grain size d50 on the dynamic G and its degradation rule for calcareous sand, a set of resonant column tests is conducted on calcareous sand with different grain-size-distribution curves. The experimental results clearly show that the G degrades faster for calcareous sand with a lower sigma 0 ' and a larger Cu. By contrast, the degradation of the G is affected less by dr and d50. The G/Gmax values decreased slightly as gamma increased but remained less than 10-5, whereas the G/Gmax curve descended rapidly as gamma increased beyond 10-5. Based on the test results obtained in this study and previously published data, a new mathematical model characterizing the degradation tendency of G/Gmax with respect to the shear strain level of calcareous sands with different gradation conditions is proposed. The relevant parameters associated with the proposed model are correlated with Cu and sigma 0 '.

关键词： Shear modulus calcareous sand grain size distribution curves resonant column tests relative density

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Comprehensive floor plan vectorization with sparse point set representation

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AUTOMATION IN CONSTrUCTION 2025年 173卷

作者： Xing, Jici Wu, Longyong Zeng, Tianyi Wu, Yijie Shang, Jianga China Univ Geosci Sch Comp Sci Wuhan 430074 Peoples R China Anyang Normal Univ Sch Software Engn Anyang 455000 Peoples R China Univ Hong Kong Fac Architecture Pokfulam Hong Kong 999077 Peoples R China

Floor plan vectorization in complex scenarios poses significant challenges due to the intricate and diverse nature of design elements. This paper capitalizes on the inherent characteristics of architectural elements, eliminating the requirement for semantic segmentation processes. This paper proposes a method with a specially designed representation, employing a quartet of points to accurately capture a wide range of shapes with minimal parameters. Furthermore, a comprehensive dataset is proposed, consisting of large-scale images that contain a significantly higher number of elements and encompass diverse floor plan styles. Experimental results demonstrate the robust performance and substantial improvement of the proposed method in boundary delineation. These results indicate the ease of parameterization and notable practical potential of the proposed method in real-world scenes.

关键词： Floor plan dataset Vectorization

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Insights into small landslides inducing major disasters in the Wumeng Mountain area from the Liangshui landslide

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LANdSLIdES 2025年第3期22卷 857-875页

作者： Wang, Qiankuan Xing, Aiguo Liao, Liangbo Liu, Yiwei Zhuang, Yu Shanghai Jiao Tong Univ State Key Lab Ocean Engn Shanghai 200240 Peoples R China Shanghai Huace Nav Technol Ltd Shanghai 201702 Peoples R China

The Wumeng Mountain area in china is highly susceptible to landslides due to tectonic movements, heavy monsoon rains, and human activities. despite their small size, these landslides can cause significant damage. The 2024 Liangshui landslide, with a volume of about 70,000 m3, resulted in 44 fatalities and marked the third major winter geological disaster in the Zhenxiong range in recent years. Comprehensive research on this landslide is crucial for understanding its triggers and failure mechanisms. Using the rapid Mass Movement Simulation dynamic model and remote sensing data, we analyzed the dynamic evolution of the Liangshui landslide, following a thorough survey of its characteristics and potential failure mechanisms. Our findings indicate that landslide-prone strata, fractured rock, and steep source areas provided the necessary material and mechanical foundation. Seepage of fracture water after a prolonged precipitation softened the rock mass and decreased slope stability. A sudden drop in temperature and snowfall caused frost heave, leading to the expansion of rock fractures and ultimately triggering the landslide. This research provides insight into how small landslides can induce major disasters in the Wumeng Mountain area, as well as those triggered by prolonged rainy (or snowy) conditions in Zhenxiong County.

关键词： Liangshui landslide rAMMS dynamic model Small landslides inducing major disasters Prolonged low-intensity rainfall (or snowfall)

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Characterization, Optimization, and Scaling-up of Submerged Inonotus hispidus Mycelial Fermentation for Enhanced Biomass and Polysaccharide Production

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APPLIEd BIOCHEMISTrY ANd BIOTECHNOLOGY 2025年第3期197卷 1534-1555页

作者： Shen, Ke Liu, Yuanshuai Liu, Liyan Khan, Abdul Waheed Normakhamatov, Nodirali Wang, Zhaomei South China Univ Technol Sch Food Sci & Engn Guangzhou 510640 Peoples R China Hong Kong Univ Sci & Technol Dept Chem & Biol Engn Hong Kong 999077 Peoples R China Minist Hlth Uzbekistan Tashkent Pharmaceut Inst Tashkent 100015 Uzbekistan Res Inst Food Nutr & Human Hlth Guangzhou Peoples R China

This study was to establish an efficient strategy based on inoculum-morphology control for the submerged mycelial fermentation of an edible and medicinal fungus, Inonotus hispidus. Two major morphological forms of the mycelial inoculum were compared, dispersed mycelial fragments versus aggregated mycelial clumps. The dispersed one was more favorable for the fermentation, starting with a shorter lag period and attaining a higher biomass yield and more uniform mycelium pellets in shake flasks. The mycelial pellets taken from the shake flask culture on day 6 were fragmented at 26,000 rpm in a homogenizer, and a shear time of 3 min provided the optimal inoculum. The inoculum and culture conditions were further verified in 5-L stirred tank fermenters and then the fermentation was scaled-up in a 100-L stirred tank. With the optimized inoculum and process conditions plus a fed-batch operation, much higher productivities, including 22.23 g/L biomass, 3.31 g/L EPS, and 5.21 g/L IPS, were achieved in the 100-L fermenter than in the flask culture. A composition analysis showed that the I. hispidus mycelium produced by the fermentation was rich in protein, dietary fiber, and polysaccharides which may be beneficial to health. Overall, the results have shown that the inoculum characteristics including age, morphology, and state of aggregation have significant impact on the productivity of mycelial biomass and polysaccharides in a submerged mycelial fermentation of the I. hispidus fungus.

关键词： Inonotus hispidus Polysaccharides Mycoprotein Morphology Submerged fermentation Fed-batch cultivation

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Effect of alumina fibers on microstructure and mechanical properties of composite enamel coatings

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Ceramics International 2025年第14期51卷 18865-18876页

作者： Chen, Xueying Guo, Yan Gao, Xinrui Shi, Shiyan Sun, dongguang Jia, Xiaoyun Jiang, Weizhong Luo, Lida Wang, Qingwei State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and Engineering Donghua University Shanghai201620 China Engineering Research Center of Advanced Glass Manufacturing Technology Ministry of Education Donghua University Shanghai201620 China Key Laboratory of Special Glass and Enamel for China Light Industry Donghua University Shanghai201620 China Qingdao Haier Intelligent Cooking Appliances Co. Ltd China

Glass enamel coatings are widely used to protect metal against corrosion and weathering due to their exceptional chemical stability. However, the application potential of enamel coatings will be further enhanced if their mechanical properties, particularly impact resistance and toughness, can be improved. In this study, we investigated the influence of varying amounts of alumina fibers on the microstructure, phase composition, and mechanical properties of enamel coatings by fabricating composite enamel coatings. The impact strength, hardness and modulus of the resulting materials were evaluated by falling ball impact tests and nanoindentation tests. The results showed that the alumina fibers were well bonded to the enamel matrix, and the coating surface roughness and contact angle increased with fiber addition. The coating had the lowest porosity and best impact resistance at 0.5 wt% fiber addition. At this point, the modulus and hardness of the composite enamel coating demonstrated improved stability, with the overall hardness reaching its maximum value, and excessive addition of alumina fibers can lead to a reduction in coating performance. As a result, the alumina fibers appear feasible to use as reinforcing material to produce high performance composite enamel coatings. © 2025 Elsevier Ltd and Techna Group S.r.l.

关键词： rockwell hardness

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reliability evaluation of the grabbing, positioning, and release mechanism for gravitational wave detection

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PrOCEEdINGS OF THE INSTITUTION OF MECHANICAL ENGINEErS PArT O-JOUrNAL OF rISK ANd rELIABILITY 2025年

作者： Mei, Guangyao Wang, Ke Wu, Yuwei Hu, Jinbo Yang, Fei Zhang, Jinxiu Wu, Jianing Sun Yat Sen Univ Sch Aeronaut & Astronaut Shenzhen Campus66 Gongchang Rd Shenzhen 518107 Peoples R China Shanghai Acad Spaceflight Technol Shanghai Inst Spacecraft Equipment Shanghai Peoples R China Sun Yat Sen Univ Sch Adv Mfg Shenzhen Campus66 Gongchang Rd Shenzhen 518107 Peoples R China China Univ Geosci Beijing Sch Engn & Technol Beijing Peoples R China Harbin Inst Technol State Key Lab Robot & Syst Harbin Peoples R China

Predicting reliability is an essential part of the design phase for ensuring mission success. In the realm of gravitational wave detection, the integrity and dependability of the Grabbing, Positioning, and release Mechanism (GPrM) are paramount for its effective space-based deployment. However, predicting reliability of a complex mechanical system like the GPrM during the design phase poses significant challenges due to the harsh and variable conditions of the space environment. This paper addresses these challenges by proposing a reliability evaluation method that combines the stochastic and degradation characteristics of the GPrM, according to which both randomness of the stud position and the degradation of the piezoelectric coefficient are considered. Failure criteria are established based on mission performance indicators, and the Kaplan-Meier estimator is used to analyze the mechanism reliability of the GPrM over time. The result predicts that the reliability of the GPrM is around 0.8 after 107 operating cycles. This finding demonstrates that our proposed method is an effective approach for evaluating reliability, offering valuable insights for ensuring the long-term performance and successful operation of precision mechanisms.

关键词： release mechanisms reliability analysis dynamic performance gravitational wave detection piezoelectric coefficient degradation

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reinforcement Learning Based Motion Control Method for Electrical-hydraulic Valve-Controlled System

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IEEE-ASME TrANSACTIONS ON MECHATrONICS 2025年第1期30卷 751-762页

作者： Gao, Lulu Zhao, Jixing duan, Jingliang Liu, Shaowei Ma, Fei Univ Sci & Technol Beijing Sch Mech Engn Beijing 100083 Peoples R China Univ Sci & Technol Beijing Shunde Innovat Sch Foshan 528399 Peoples R China

The automation and intelligence development of heavy-duty mobile machines and industrial equipment require the accurate control of electrical-hydraulic valve-controlled system (EHVS). This article presented a generic reinforcement learning with predictive target information control (rLPC) method for EHVS to improve the control accuracy, in which a distributional soft actor-critic (dSAC) iteration frame was established. First, a dynamic model considering nonlinearity, saturation, and uncertainty from a time-varying system perspective was established and validated through tests under typical conditions. Then the model-free rLPC method was designed for EHVS. As the baseline, the classical proportional-integral-derivative (PId) and an adaptive PId (APId) with rL-tuning were designed for comparison purposes. Finally, the corresponding iteration frame was established to improve the performance of rL-related works in the designed control methods with dSAC. The comparison results during typical operations show that the proposed rLPC method can handle dynamic response and steady errors better at different states of the system and actuator. The effects of the predictive horizon on control performance were also revealed. The stability of the method was also validated with a designed instantiating EHVS, specifically a hydraulic inverted pendulum system. The performance of the proposed methods was quantitatively analyzed with the normalizing performance indicator rho. The mean value of the indicator was about 0.0028, which is lower than the first two methods and the existing control method for EHVS.

关键词： Valves Hydraulic systems Actuators Friction Bars reinforcement learning Time-varying systems Adaptive proportional-integral-derivative (APId) electrical-hydraulic valve-controlled system (EHVS) reinforcement learning (rL) reinforcement learning with predictive target information control (rLPC)

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Characterization and discrimination of rhus chinensis Mill. honeys from different geographical origins based on physicochemical parameters, minerals, volatile compounds and antioxidant activities

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JOUrNAL OF FOOd MEASUrEMENT ANd CHArACTErIZATION 2025年第5期19卷 3581-3599页

作者： Lin, Congcong Chen, Chiqing Liu, Yiwen Liu, rui Lu, Qun Huazhong Agr Univ Coll Food Sci & Technol Wuhan 430070 Peoples R China Wuhan Engn Res Ctr Bee Prod Qual & Safety Control Wuhan 430070 Peoples R China Wufeng Chicheng Biotech Co Ltd Yichang 443400 Peoples R China Wufeng Tujia Autonomous Cty Publ Inspection & Test Yichang 443400 Peoples R China Huazhong Agr Univ Key Lab Environm Correlat Dietol Minist Educ Wuhan 430070 Peoples R China

This study aims to characterize and discriminate rhus chinensis Mill. honeys from different geographical origins based on their physicochemical parameters, mineral elements, volatile compounds, and antioxidant activities. rhus chinensis Mill. honey samples were collected from four different geographical origins for analysis. The results demonstrated statistical differences in nine physicochemical parameters, nine mineral elements, 12 volatile compounds, total phenolic content (TPC), and antioxidant activities of rhus chinensis Mill. honey from different origins. The principal component analysis (PCA) biplot and partial least squares-discriminate analysis (PLS-dA) plot constructed with 35 statistically different variables demonstrated that different origins of rhus chinensis Mill. honey could be effectively discriminated, among which 14 variables had variable importance in projection (VIP) > 1. These variables could serve as potential markers to discriminate rhus chinensis Mill. honey from different origins. Our findings improve the understanding of rhus chinensis Mill. honey and can facilitate the tracing of its origin.

关键词： rhus chinensis Mill. honey Geographical origin Mineral elements Aroma characteristics Antioxidant activity Multivariate analysis

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Model-data Hybrid driven Control of Hydraulic Euler-Lagrange Systems

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IEEE-ASME TrANSACTIONS ON MECHATrONICS 2025年第1期30卷 131-143页

作者： Yao, Zhikai Liang, Xianglong Wang, Shuping Yao, Jianyong Nanjing Univ Posts & Telecommun Coll Automat Nanjing 210023 Peoples R China Nanjing Univ Posts & Telecommun Coll Artificial Intelligence Nanjing 210023 Peoples R China Nanjing Univ Sci & Technol Sch Mech Engn Nanjing 210094 Peoples R China Nanjing Univ Inst Acoust Nanjing 210093 Peoples R China Nanjing Univ Sch Phys Nanjing 210093 Peoples R China

As hydraulic Euler-Lagrange systems evolve to encompass high-dimension and intricate structures, the formulation of the mechanical dynamics model becomes impractical, even though the hydraulic dynamic information remains accessible. In this article, we make the first attempt to establish model-data hybrid driven controller for hydraulic Euler-Lagrange systems. The proposed strategy commences with the formulation of model-based nonlinear robust controller, followed by the introduction of actor-critic reinforcement learning to effectively tackle uncertainties associated with unknown mechanical dynamics. Employing Lyapunov analysis, we have proven the asymptotic stability of the model-based nonlinear robust controller, along with the convergence and (sub)optimality of the introduced actor-critic reinforcement learning. Building upon this foundation, the newly devised hybrid-driven controller still guarantees asymptotic stability through the reconstruction of the error auxiliary function. We validated the efficacy of the proposed strategy on a well-established six-degree-of-freedom hydraulic manipulator and conducted a comparative analysis with the purely data-driven approach to demonstrate the superior performance of the developed controller. The integration of model-based and data-driven terms in our strategy signifies notable advancements in the control paradigm for hydraulic Euler-Lagrange systems, and the conceptual control framework also holds the potential to address control challenges within diverse and intricate industrial systems.

关键词： Euler-Lagrange systems hydraulic systems nonlinear control reinforcement learning robust control

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