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Journal of Renewable Materials 2025年第2期13卷 363-383页

作者： Martin Böhm MilošJerman Martin Keppert Klára Kobetičová Dana Koňáková Milena Pavlíková RobertČerný Department of Materials engineering and Chemistry Faculty of Civil EngineeringCzech Technical University in PragueThákurova 7Prague16629Czech Republic

The effect of using 2%and 10%sodium hydroxide solution as surface treatment of rape straw on its water vapor adsorption properties is analyzed in the relative humidity(RH)range of 0%to 98%.Scanning electron microscopy(SEM),energy dispersive spectroscopy(EDS),and Fourier-transform infrared spectroscopy(FTIR)are used to investigate the morphological,chemical and structural changes of the treated straw *** mineral particles formed on the surface after the treatment are analyzed using X-ray diffraction(XRD).The application of sodium hydroxide solution results in the disruption of the straw *** the concentration of sodium hydroxide increases,the disruption of the straw surface increases,and the ability of the straw to adsorb water vapor also increases over the entire RH *** addition to the surface disruption and chemical changes caused by the alkaline treatment,the differences in the equilibrium moisture content of treated and untreated rape straw can also be attributed to the formation of minerals on the straw surface,namely calcite for the 2%sodium hydroxide solution,and gaylussite and thermonatrite for the 10%solution.

关键词： Modification of straw surface alkaline treatment sorption mechanism Guggenheim-Anderson-de Boer model(GAB)

An extended discontinuous deformation analysis for simulation of grouting reinforcement in a water-rich fractured rock tunnel

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Journal of Rock Mechanics and Geotechnical engineering 2025年第1期17卷 168-186页

作者： Jingyao Gao Siyu Peng Guangqi Chen Hongyun Fan Department of civil and Structural engineering Kyushu UniversityFukuoka819-0395Japan School of Resources and Safety engineering Central South UniversityChangshaHunan410083China School of civil and Transportation engineering Hebei University of TechnologyTianjin300401China School of Qilu Transportation Shandong UniversityJinanShandong250000China

Grouting has been the most effective approach to mitigate water inrush disasters in underground engineering due to its ability to plug groundwater and enhance rock ***,there is a lack of potent numerical tools for assessing the grouting effectiveness in water-rich fractured *** this study,the hydro-mechanical coupled discontinuous deformation analysis(HM-DDA)is inaugurally extended to simulate the grouting process in a water-rich discrete fracture network(DFN),including the slurry migration,fracture dilation,water plugging in a seepage field,and joint reinforcement after *** validate the capabilities of the developed method,several numerical examples are conducted incorporating the Newtonian fluid and Bingham *** simulation results closely align with the analytical ***,a set of compression tests is conducted on the fresh and grouted rock specimens to verify the reinforcement method and calibrate the rational properties of reinforced *** engineering-scale model based on a real water inrush case of the Yonglian tunnel in a water-rich fractured zone has been *** model demonstrates the effectiveness of grouting reinforcement in mitigating water inrush *** results indicate that increased grouting pressure greatly affects the regulation of water outflow from the tunnel face and the prevention of rock detachment face after excavation.

关键词： Discontinuous deformation analysis(DDA) Water-rich fractured rock tunnel Grouting reinforcement Water inrush disaster

Anisotropy characterization of upper shanghai clays: Shear strength and small-strain stiffness

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Journal of Rock Mechanics and Geotechnical engineering 2025年第1期17卷 493-508页

作者： Lixin Lan Wenxuan Zhu Guanlin Ye Qi Zhang Tongshuai Yang Department of civil engineering State Key Laboratory of Ocean EngineeringShanghai Key Laboratory for Digital Maintenance of Buildings and InfrastructureShanghai Jiao Tong UniversityShanghai200240China Department of civil engineering Shanghai Jiao Tong UniversityShanghai200240China The Fourth Construction Co. Ltd.of China Construction Eighth Engineering DivisionQingdao266100China

Comprehensive investigations have been conducted to study the structure and overconsolidation of upper Shanghai clays, i.e. Layers 2–6 clays, typically located at depths of 30–40 m. However, limited information is available on their anisotropy, and even less is known about the correlation between structure, overconsolidation, and anisotropy. In this study, the undrained anisotropy characteristics of shear strength and small-strain shear stiffness in upper Shanghai Layers 2–6 clays were thoroughly assessed using a series of K0-consolidated undrained triaxial compression (TC) and triaxial extension (TE) tests (K0 is the coefficient of lateral earth pressure at rest). The effective stress paths, shear strength, and small-strain shear stiffness from the undrained TC and TE tests demonstrate the anisotropic behaviors in upper Shanghai clays. Analyses of data from upper Shanghai clays and other clays worldwide indicate that the shear strength anisotropy ratio (Ks) converges at 0.8 as the overconsolidation ratio (OCR) and plasticity index (Ip) increase, while the small-strain shear stiffness anisotropy ratio (Re) converges at 1.0. The influence of OCR on Ks and Re is more pronounced than that of Ip and sensitivity (St). Nevertheless, no clear correlation between Ks and Re is observed in upper Shanghai clays.

关键词： Shanghai clays Anisotropy Shear strength Small-strain stiffness

Evolution of the elastic properties of lacustrine organic shales under different thermal maturity conditions

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Science China Earth Sciences 2025年第3期68卷 781-802页

作者： Zhenjia CAI Luanxiao ZHAO Jiqiang MA Fengshou ZHANG Jianhua GENG State Key Laboratory of Marine Geology Tongji University School of Ocean and Earth Science Tongji University Department of Geotechnical engineering College of civil engineering Tongji University

Research on the elastic responses of organic-rich shales during thermal evolution has predominantly focused on North American marine shales. However, the rock physics properties of lacustrine(continental) organic-rich shales with varying maturities, particularly under the unique geological conditions in China, have not yet been comprehensively explored. Therefore,characterizing the elastic properties of lacustrine organic-rich shales across various maturity stages is crucial for understanding their seismic rock physics responses and for enabling the identification of sweet spots in continental shale reservoirs using logging and seismic data, as well as facilitating geophysical monitoring of the in-situ conversion of oil shales. In this study,hydrous pyrolysis experiments were conducted on immature shales from the Chang 7 member of the Yanchang Formation in the Ordos Basin and the Jijuntun Formation in the Fushun Basin. Compressional and shear wave velocities, along with elastic anisotropy, were measured at various stages of thermal maturity to observe the evolution of the elastic properties. For the Chang7 shale(compacted shale), both P-and S-wave velocities perpendicular to the bedding decreased significantly during the oil and gas generation stages, with the S-wave velocity perpendicular to the bedding decreasing by over 40%. Meanwhile, the elastic anisotropy increased significantly, likely because of microcracks formed by hydrocarbon expulsion from the bedding-parallel organic matter. In contrast, the Jijuntun Formation shale(cemented shale) exhibited an increase in both P-and S-wave velocities during the oil generation stage. This trend could be attributed to early-stage cementation, which suppressed microcrack formation, while the increase in the elastic modulus of the organic matter became dominant. However, during the gas generation stage, both velocities decreased, while the anisotropy increased owing to the growth of organic pores and microcracks, which out

关键词： Lacustrine shales Thermal pyrolysis Elastic wave velocity Anisotropy In-situ conversion

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Balancing charge carrier density and exciton recombination in defective g-C3N4 for efficient photocatalytic hydrogen evolution

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Progress in Natural Science:Materials International 2025年第01期 238-244页

作者： Peng Wu Tao Zhou Zhongqiu Tong Fengshuo Xi Jijun Lu Xiufeng Li Wenhui Ma Shaoyuan Li Xingwei Yang faculty of Metallurgical and Energy engineering Kunming University of Science and Technology School of engineering Yunnan University

Graphitic carbon nitride（g-C3N4） is a promising material for photocatalytic hydrogen production owing to its tunable band structure and high charge carrier density, however, it displays a high carrier recombination *** engineering can solve this problem by providing active sites within g-C3N4to accelerate the separation of photogenerated electrons and holes and enhance its solar light absorption. Previous studies have implied that there exists a defect concentration threshold for obtaining the maximum photocatalytic hydrogen production performance, but the underlying mechanism remains unclear. In this study, the relationship between charge carrier density and exciton recombination was investigated to address this issue. A series of g-C3N4photocatalysts with different tri-coordinate nitrogen（N3C） vacancy concentrations were synthesized using in-situ coprecipitation polymerization. The catalytic performance is related to the vacancy concentration, higher vacancy concentration will lead to higher carrier separation efficiency and carrier density of g-C3N4, as well as better photocatalytic hydrogen production performance. However, when excessive vacancies act as recombination centers, the charge carrier recombination rate is increased, which will also adversely affect the photocatalytic hydrogen production performance.

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Discovering causal models for structural,construction and defense-related engineering phenomena

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Defence Technology(防务技术) 2025年第1期43卷 60-79页

作者： M.Z.Naser School of civil&Environmental engineering and Earth Sciences(SCEEES) Clemson UniversityClemsonSouth Carolina 29634USA The Artificial Intelligence Research Institute for Science and engineering(AIRISE) Clemson UniversityClemsonSouth Carolina 29634USA

Causality,the science of cause and effect,has made it possible to create a new family of *** models are often referred to as causal *** those of mathematical,numerical,empirical,or machine learning(ML)nature,causal models hope to tie the cause(s)to the effect(s)pertaining to a phenomenon(i.e.,data generating process)through causal *** paper presents one of the first works at creating causal models in the area of structural and construction *** this end,this paper starts with a brief review of the principles of causality and then adopts four causal discovery algorithms,namely,PC(Peter-Clark),FCI(fast causal inference),GES(greedy equivalence search),and GRa SP(greedy relaxation of the sparsest permutation),have been used to examine four phenomena,including predicting the load-bearing capacity of axially loaded members,fire resistance of structural members,shear strength of beams,and resistance of walls against impulsive(blast)*** from this study reveal the possibility and merit of discovering complete and partial causal ***,this study also proposes two simple metrics that can help assess the performance of causal discovery algorithms.

关键词： Causality Causal discovery Directed acyclic graphs Machine learning Metrics

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Application of a multi-monitoring system and its temperature correction

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Journal of Mountain Science 2025年第2期22卷 681-694页

作者： LIU Songyuan YANG Peixi HE ManChao TAO Zhigang State Key Laboratory for Tunnel engineering China University of Mining and Technology-BeijingBeijing 100083China School of Mechanics and civil engineering China University of Mining and Technology-BeijingBeijing 100083China College of Mining engineering North China University of Science and TechnologyTangshan 063210China

The Dazu Rock Carvings in Chongqing were inscribed on the World Heritage List in *** recent years,the Dazu Rock Carvings have faced environmental challenges such as geological forces,increased precipitation,pollution and tourism,which have led to rock deterioration and structural *** multi-source monitoring system for the protection of the rock carvings,based on the Internet of Things,includes Global Navigation Satellite System(GNSS)displacement monitoring,static level displacement monitoring,laser rangefinder displacement monitoring,roof pressure sensor monitoring and environmental damage *** paper analyses data from each sub-monitoring system within the multi-source monitoring system applied to Yuanjue Cave in the Dazu Rock ***,a correlation analysis between climate monitoring data and roof displacement data was carried out to assess the effect of *** on the results of the analysis,a temperature correction equation for the laser rangefinder was derived to improve the laser rangefinder displacement monitoring *** improved system was then used to monitor Cave 168,revealing the deformation and erosion patterns of the *** research results demonstrate that the multiparameter monitoring system is capable of accurately measuring and analyzing the stability of the Dazu stone carvings,as well as the effects of environmental conditions on *** use of the Internet of Things(IoT)and real-time data collection to monitor rock deformation and environmental conditions is an innovative application of technology in cultural heritage *** of the monitoring system and statistical correlation analysis of temperature and laser rangefinder data highlight the thoroughness of the methodology in this paper and its relevance to sustainable mountain *** the future,multi-source monitoring systems will have a broader application in the conservation of other UNESCO World Heritage Sites.

关键词： Multi-source Monitoring System Data Fitting Dazu Rock Carvings Rock Cave Protection

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Effect of Cu/HZSM-5 sorbents with different Si/Al ratios on the adsorption and oxidation performance of H_(2)S

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Journal of Environmental Sciences 2025年第5期151卷 161-173页

作者： Kaini Ma Kai Li Ping Ning Jiayu Feng Jiacheng Bao Lei Shi Xiangyu Wang Xin Sun faculty of Environmental Science and engineering Kunming University of Science and TechnologyKunming 650500China National-Regional engineering Center for Recovery of Waste Gases from Metallurgical and Chemical Industries Kunming University of Science and TechnologyKunming 650500China

This study employed a wet impregnation method to synthesize five types of Cu/HZSM-5 adsorbents with Si/Al ratios of 25,50,85,200,and 300,used for the removal of H_(2)S in lowtemperature,low-oxygen *** impact of different Si/Al ratios on the adsorption oxidative performance of Cu_(30)/HZSM-5–85 adsorbents was *** to the performance test results,Cu_(30)/HZSM-5–85 exhibited the highest breakthrough capacity,reaching 231.75 mg H_(2)S/g_(sorbent).Cu/HZSM-5 sorbent maintains a strong ability to remove H_(2)S even under humid conditions and shows excellent water ***,BET,and XPS results revealed that CuO is the primary active species,with Cu_(30)/HZSM-5–85 having the largest surface area and highest CuO content,providing more active sites for H_(2)S adsorption.H_(2)-TPR and O_(2)-TPD results confirmed that Cu_(30)/HZSM-5–85 sorbent exhibits outstanding redox properties and oxygen storage capacity,contributing to excellent oxygen transferability in the molecular sieve adsorption-oxidation *** notable characteristics such as a large surface area,high desulfurization efficiency,and water resistance,Cu_(30)/HZSM-5–85 sorbents hold significant importance for industrial applications.

关键词： H_(2)S Si/Al ratio Adoration-oxidation Cu/HZSM-5-85(HZSM-5 with Si/Al ratio of 85 loaded Cu)

Investigation of magnesium phosphate cement on river dredged sludge with varying humic acid content and solidification mechanism

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Journal of Rock Mechanics and Geotechnical engineering 2025年第1期17卷 573-585页

作者： Xiaoyi Yuan Lei Peng Bing Chen Department of civil engineering Shanghai Jiao Tong UniversityShanghai200240China State Key Laboratory of Ocean engineering Shanghai Jiao Tong UniversityShanghai200240China

This paper investigated the use of magnesium phosphate cement (MPC) for solidifying sludge with different humic acid (HA) content (ranging from 0 to 4.5%) and explored the solidification mechanism. Fluidity, setting time, unconfined compressive strength (UCS), the strength formation mechanism, and the spontaneous imbibition process of solidified sludge (SS) were studied. The results indicate that MPC can be used as a low-alkalinity curing agent. As the HA content increases, fluidity and setting time also increase, while hydration temperature and strength decrease. Additionally, the failure mode of SS transitions from brittleness to ductility. The strength of SS is composed of the cementation strength provided by MPC hydration products, matric suction, osmotic suction, and the structural strength of the sludge. MPC reduces the structural strength caused by the shrinkage of pure sludge under the action of matric suction, but the incorporation of MPC significantly improved the strength when the sludge is eroded by water. X-ray diffraction (XRD) and scanning electron microscopy (SEM) show that the sludge and MPC can form a dense solid body, forming various hydration products, and synergistically improve the mechanical properties of the sludge.

关键词： Sludge solidification MPC Unsaturated spontaneous imbibition Strength mechanism Humic acid

Exit options sustain altruistic punishment and decrease the second-order free-riders, but it is not a panacea

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Science China(Information Sciences) 2025年第1期68卷 278-291页

作者： Chen SHEN Zhao SONG Lei SHI Jun TANIMOTO Zhen WANG faculty of engineering Sciences Kyushu University School of Statistics and Mathematics Yunnan University of Finance and Economics School of Computing Engineering and Digital Technologies Teesside University School of Artificial Intelligence OPtics and Electro Nics (iOPEN) Northwestern Polytechnical University

Why do humans punish free riders at their own expense? This behavior represents an evolutionary puzzle in human societies. This study explores the role of exit strategies in fostering altruistic punishment within evolutionary game theory. We extend the traditional prisoner's dilemma model by incorporating exiters, players who opt out for a small payoff while nullifying their opponent's payoff, and altruistic punishers who cooperate and punish non-cooperators. Our findings indicate that in well-mixed populations, exiters destabilize defection but do not promote altruistic punishment. In social networks, however,exiters enable altruistic punishment via cyclic dominance among altruistic punishers, defectors, and exiters. Notably, this cyclic dominance is sensitive to exit payoffs; adjustments can lead to cyclic dominance of non-punishing cooperators, defectors, and exiters, or to a bi-stable state between these two types of cyclic dominance. These results highlight the nuanced impact of exiters on altruistic punishment, emphasizing the need for careful incentivization of exit behavior. While exiters can support altruistic punishment in networked populations, their effectiveness is not a panacea and is highly sensitive to exit payoffs, indicating limits to the voluntary participation mechanism.

关键词： evolutionary game theory altruistic punishment coexistence cyclic dominance bi-stable