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Saturated Alcohols Electrocatalytic Oxidations on Ni-Co Bimetal Oxide Featuring Balanced B-and L-Acidic Active Sites
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作者 Junqing Ma Wenshu Luo +9 位作者 Xunlu Wang Xu Yu Jiacheng Jayden Wang Huashuai Hu Hanxiao Du Jianrong Zeng Wei Chen Minghui Yang Jiacheng Wang Xiangzhi Cui 《Nano-Micro Letters》 2026年第2期105-123,共19页
Investigating structural and hydroxyl group effects in electrooxidation of alcohols to value-added products by solid-acid electrocatalysts is essential for upgrading biomass alcohols.Herein,we report efficient electro... Investigating structural and hydroxyl group effects in electrooxidation of alcohols to value-added products by solid-acid electrocatalysts is essential for upgrading biomass alcohols.Herein,we report efficient electrocatalytic oxidations of saturated alcohols(C_(1)-C_(6))to selectively form formate using Ni Co hydroxide(Ni Co-OH)derived Ni Co_(2)O_(4)solid-acid electrocatalysts with balanced Lewis acid(LASs)and Brønsted acid sites(BASs).Thermal treatment transforms BASs-rich(89.6%)Ni Co-OH into Ni Co_(2)O_(4)with nearly equal distribution of LASs(53.1%)and BASs(46.9%)which synergistically promote adsorption and activation of OH-and alcohol molecules for enhanced oxidation activity.In contrast,BASs-enriched Ni Co-OH facilitates formation of higher valence metal sites,beneficial for water oxidation.The combined experimental studies and theoretical calculation imply the oxidation ability of C1-C6alcohols increases as increased number of hydroxyl groups and decreased HOMO-LUMO gaps:methanol(C_(1))<ethylene glycol(C_(2))<glycerol(C3)<meso-erythritol(C4)<xylitol(C5)<sorbitol(C6),while the formate selectivity shows the opposite trend from 100 to 80%.This study unveils synergistic roles of LASs and BASs,as well as hydroxyl group effect in electro-upgrading of alcohols using solid-acid electrocatalysts. 展开更多
关键词 Solid-acid electrocatalyst Alcohol oxidation reaction Bronsted acid sites Lewis acid sites C_(1)-C_(6)saturated alcohols
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Hydrochar effects on the microstructure and hydromechanical behaviour of unsaturated compacted soils
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作者 Huan Dong Anthony Kwan Leung +2 位作者 Jianbin Liu Ali Akbar Karimzadeh Rui Chen 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第9期6045-6053,共9页
The effectiveness of using vegetation to stabilise shallow soil slopes heavily depends on the survival of vegetation,yet the amplification of extreme events induced by climate change threatens the health of plants cov... The effectiveness of using vegetation to stabilise shallow soil slopes heavily depends on the survival of vegetation,yet the amplification of extreme events induced by climate change threatens the health of plants covering slopes.Hydrochar is an environmentally friendly soil amender that can achieve the potential benefits of promoting plant growth for slope stabilisation and facilitation of waste upcycling.The mechanism underlying the hydrochar effects on the mechanical behaviour of unsaturated soils remains unclear.This study investigated the influence of grass-derived hydrochar on the water retention,compressibility,and shear strength of a compacted siltyeclay sand.Soil microstructural changes due to hydrochar amendment were measured to explain the soilehydrochar hydromechanical interaction.The increase in suction resulted in a less significant increase in yield stress and a negligible reduction in compressibility of the hydrochar-amended soil compared with the unamended case.This phenomenon was observed because hydrochar addition reduced the large pores with diameters greater than the macropore peak of 60 mm due to pore filling by hydrochar particles,resulting in a less substantial volume contraction during drying.Hydrochar introduced more significant effects on the soil’s shear strength in an unsaturated state compared to a saturated case.Despite the similarity of the unsaturated amended soil with the critical-state friction angle to the saturated case,the former exhibited a greater shear strength because the hydrochar addition improved water retention capability.As a result,the degree of saturation and,hence,Bishop’s effective stress were higher than those for the unamended case for a given suction. 展开更多
关键词 Hydrochar saturated soils Unsaturated soils Mechanical behaviour Triaxial tests Critical state
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Impact of flow direction on suffusion of sand-clay mixtures under variably saturated conditions
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作者 Yerim Yang Hangseok Choi +2 位作者 Jooho Lee Yongjoon Choe Jongmuk Won 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第4期2511-2525,共15页
Suffusion is the process defined as the migration of relatively small soil particles through the pores of a soil matrix composed of relatively large particles,driven by substantial hydrodynamic forces and weak attract... Suffusion is the process defined as the migration of relatively small soil particles through the pores of a soil matrix composed of relatively large particles,driven by substantial hydrodynamic forces and weak attraction energies.This study investigates the influence of flow direction(upward and downward)on suffusion induced by interaction energies in sand-clay mixtures under both saturated and unsaturated conditions.The impact of clay mineralogy(kaolinite,illite,and montmorillonite),sand-grain size,and ionic concentration(IC)gradient were discussed based on the observed breakthrough curves(BTCs)and relative saturation rate(Sr)during injection(particularly for unsaturated conditions).Under saturated conditions,higher susceptibility to suffusion was observed in sand-kaolinite and sand-illite mixtures under downward flow compared to upward flow,whereas the suffusion of montmorillonite was more significant under upward flow than under downward flow.In contrast,for unsaturated conditions,more substantial suffusion of kaolinite and illite particles occurred under upward flow compared to downward flow,whereas the opposite trend was observed in sand-montmorillonite mixtures.In addition,the impact of sand-grain size(or the size ratio between sand and clay)on the suffusion of kaolinite and illite under unsaturated conditions suggests a reduced size ratio that leads to relatively significant suffusion under downward flow compared to upward flow.The findings presented in this study contribute to a comprehensive understanding of the influence of flow direction on suffusion in sand-clay mixtures under both saturated and unsaturated conditions. 展开更多
关键词 Suffusion Breakthrough curve(BTC) Sand-clay mixture saturated soil Unsaturated soil Ionic concentration(IC) Flow direction Clay mineralogy
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Exponential Stability of Impulsive System via Saturated Sliding Mode Control
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作者 Miaomiao Yu Xiaodi Li 《IEEE/CAA Journal of Automatica Sinica》 2025年第2期469-471,共3页
Dear Editor,This letter presents a class of saturated sliding mode control (SMC)strategy for linear systems subject to impulsive disturbance and input saturation. To ensure the feasibility of proposed SMC under satura... Dear Editor,This letter presents a class of saturated sliding mode control (SMC)strategy for linear systems subject to impulsive disturbance and input saturation. To ensure the feasibility of proposed SMC under saturation, a relationship is established among attraction domain, saturation structure and control gain. 展开更多
关键词 linear systems attraction domain saturated sliding mode control impulsive disturbance saturation structure exponential stability impulsive system
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Understanding the technological aspects of Hybrid Gel as a substitute for saturated fat in processed food products
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作者 Harsh B.Jadhav 《Grain & Oil Science and Technology》 2025年第1期55-63,共9页
Hybrid Gel is the emerging soft matter in food applications that attracted the attention of food scientists owing to its beneficial characteristics as a substitute for saturated fat.The beneficial characteristics like... Hybrid Gel is the emerging soft matter in food applications that attracted the attention of food scientists owing to its beneficial characteristics as a substitute for saturated fat.The beneficial characteristics like good rheological,mechanical,thermal,and oxidative stability can be achieved using proper synergism between the individual phases.The variation in the oleogel/hydrogel phases can affect the mechanical strength of Hybrid Gel;an increase in the oleogel phase enhances the strength of Hybrid Gel.The incorporation of components like nanoparticles and colloidal particles further strengthens the gel system by enhancing the storage modulus,gel stability,oil-holding capacity,firmness,and hardness.Such Hybrid Gels can be used as a substitute for saturated fat that gives good functional,textural,and sensory attributes to the final product as compared with the saturated fat and has received positive consumer acceptance.The main objective of this concise review is to explore Hybrid Gel,understand conventional and unconventional Hybrid Gel systems,their important characteristics,and their application as a potential substitute for saturated fat in processed food products. 展开更多
关键词 Hybrid gel Oleogel HYDROGEL Oleogelator HYDROGELATOR saturated fat
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Modelling gas diffusion in compacted water-saturated Na-bentonite considering multi-porosity effects
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作者 Linyong Cui Min Chen +2 位作者 Zirui Cheng Shakil A.Masum Yanan Cui 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第11期7410-7419,共10页
Predicting the gas diffusion coefficient of water-saturated Na-bentonite is crucial for the overall performance of the geological repository for isolating high-level radioactive waste(HLW).In this study,a conceptual m... Predicting the gas diffusion coefficient of water-saturated Na-bentonite is crucial for the overall performance of the geological repository for isolating high-level radioactive waste(HLW).In this study,a conceptual model that incorporates a multi-porosity system was proposed,dividing the pore space into free water pores,interlayer water pores,and diffuse double layer(DDL)water pores,to describe the molecular diffusion behaviour of the dissolved gas in saturated bentonite.In this model,gas diffusion in these three porosities is considered as independent and parallel processes.The apparent gas diffusion coefficient is quantified by applying weighted approximations that consider the specific porosity,tortuosity factor,and constrictivity factor within each porosity domain.For verification,experimental data from gas diffusion tests on saturated MX-80 and Kunipia-F bentonite specimens across a wide range of dry densities were utilized.The proposed model could successfully capture the overall trend of the apparent gas diffusion coefficient for bentonite materials across the partial dry density of montmorillonite ranging from 900 kg/m^(3)to 1820 kg/m^(3),by employing only one fitting parameter of the scaling factor.When the partial dry density of montmorillonite decreased to 800 kg/m^(3),the proposed model shows an underestimation of the apparent gas diffusion coefficient due to possible changes of the tortuosity factor.Model predictions indicate that gas diffusion in saturated bentonite is primarily controlled by the free pore domain,with minimal contributions from DDL pores.Despite being the dominant pore type,interlayer pores contribute limitedly to total Da/Dw values due to significant constrictivity effects. 展开更多
关键词 Gas diffusion saturated bentonite MONTMORILLONITE Interlayer pore TORTUOSITY
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Investigating saturated hydraulic conductivity and its variation in a fine-grained soil with root exudates of Robinia pseudoacacia L.
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作者 Tao Xiao Ping Li +4 位作者 Liang Sun Fanyu Zhang Ji Yang Qi Gu Jiading Wang 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第11期7447-7459,共13页
Currently,Robinia pseudoacacia L.is distributed extensively across the Chinese Loess Plateau.Root exudates released by Robinia pseudoacacia L.are one of the mechanisms through which Robinia pseudoacacia L.affects soil... Currently,Robinia pseudoacacia L.is distributed extensively across the Chinese Loess Plateau.Root exudates released by Robinia pseudoacacia L.are one of the mechanisms through which Robinia pseudoacacia L.affects soil properties.However,how root exudates influencethe hydraulic properties of soil remains unclear,especially for fine-grained soils.This knowledge gap impedes a comprehensive understanding of the function of vegetation in wastewater treatment,ecological restoration,and seepage analysis.To investigate the effect and underlying mechanisms of the root exudates of Robinia pseudoacacia L.on the saturated hydraulic conductivity of loess(a fine-grainedsoil),the saturated hydraulic conductivity,bound water content,grain size distribution,and microstructure characteristics of loess treated with root exudates at varying concentrations were determined in this study through a series of tests.The results show that the mean saturated hydraulic conductivities of the loess specimens with root exudates are all lower than those without root exudates.This phenomenon can be attributed primarily to the capacity of root exudates to directly and indirectly increase the bound water content,leading to a decrease in the effective seepage channels of the loess.For loess with/without root exudates,the variation of saturated hydraulic conductivity over time can be divided into three stages:an initial constant stage,a rapid reduction stage,and a re-stabilization stage.This is primarily attributed to the migration of particles within a specifiedsize range(7-30μm)and pore-clogging in the specimens during the seepage process.A schematic diagram is proposed for the structural evolution of fine-grained soil with or without root exudates during long-term seepage. 展开更多
关键词 saturated hydraulic conductivity Root exudates Bound water Particle migration MICROSTRUCTURE
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Interfacial thermal contact model for consolidation of multilayered saturated soils subjected to time-dependent heating and loading
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作者 TANG Ke-jie WEN Min-jie +4 位作者 TU Yuan WU Wen-bing XIE Jia-hao LIU Kai-fu WU Da-zhi 《Journal of Central South University》 2025年第6期2239-2255,共17页
Heat transfers at the interface of adjacent saturated soil primarily through the soil particles and the water in the voids.The presence of water induces the contraction of heat flow lines at the interface,leading to t... Heat transfers at the interface of adjacent saturated soil primarily through the soil particles and the water in the voids.The presence of water induces the contraction of heat flow lines at the interface,leading to the emergence of the thermal contact resistance effect.In this paper,four thermal contact models were developed to predict the thermal contact resistance at the interface of multilayered saturated soils.Based on the theory of thermal-hydro-mechanical coupling,semi-analytical solutions of thermal consolidation subjected to time-dependent heating and loading were obtained by employing Laplace transform and its inverse transformation.Thermal consolidation characteristics of multilayered saturated soils under four different thermal contact models were discussed,and the effects of thermal resistance coefficient,partition thermal contact coefficient,and temperature amplitude on the thermal consolidation process were investigated.The outcomes indicate that the general thermal contact model results in the most pronounced thermal gradient at the interface,which can be degenerated to the other three thermal contact models.The perfect thermal contact model overestimates the deformation of the saturated soil during the thermal consolidation.Moreover,the effect of temperature on consolidation properties decreases gradually with increasing interfacial contact thermal resistance. 展开更多
关键词 multilayered saturated soils thermal consolidation thermal contact resistance time-dependent loading Laplace transform
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An interfacial contact model for two-dimensional thermal consolidation of multilayered saturated soils subjected to ramp-type heating
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作者 WEN Min-jie TANG Ke-jie +6 位作者 XIE Jia-hao TIAN Yi ZHANG Yi-ming WU Wen-bing MEI Guo-xiong WU Da-zhi LIU Kai-fu 《Journal of Central South University》 2025年第9期3361-3382,共22页
When the interface of a multilayered saturated soil is rough with noticeable gaps, heat flow lines converge towards the actual contact points, causing thermal flow contraction. Conversely, in the interface between two... When the interface of a multilayered saturated soil is rough with noticeable gaps, heat flow lines converge towards the actual contact points, causing thermal flow contraction. Conversely, in the interface between two layers of soil with different properties, pore water flows slowly along the pore channels, demonstrating laminar flow phenomenon. To predict the thermal contact resistance and flow contact resistance at the interface, this paper constructs general imperfect thermal contact model and general imperfect flow contact model, respectively. Utilizing a thermo-hydro- mechanical coupling model, the thermal consolidation behavior of multilayered saturated soil under two-dimensional conditions is investigated. Fourier and Laplace transformations are applied to decouple the governing equations, yielding expressions for the temperature increment, pore water pressure, and displacement in multilayered saturated soil. The inverse Fourier-Laplace transformation is then used to obtain numerical solutions, which are compared with degeneration solutions to validate the computational accuracy. The differences in the thermal consolidation process under various thermal contact and flow contact resistance models are discussed. Furthermore, the impact of parameters such as the thermal resistance coefficient, partition thermal contact coefficient, flow contact resistance coefficient, and partition flow contact coefficient on thermal consolidation are investigated. Results indicate that thermal contact resistance creates a relative thermal gradient at the interface, leading to increased pore water pressure and reduced displacement nearby. In contrast, flow contact resistance generates a relative pore pressure gradient at the interface, resulting in increased displacement within the saturated soil with minimal effect on temperature increment distribution. 展开更多
关键词 multilayered saturated soils thermal consolidation thermal contact resistance flow contact resistance ramp-type heating
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Scalable synthesis of high-purity Ti_(4)N_(3)T_(x)MXene via saturated salt solution(S^(3))etching
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作者 Yujin Chae Shi-Hyun Seok +8 位作者 Yeoseon Sim Ju-Hyoung Han Jaeeun Park Younggeun Jang Mincheal Kim Young Ho Jin EunMi Choi Zonghoon Lee Soon-Yong Kwon 《Advanced Powder Materials》 2025年第6期41-49,共9页
Two-dimensional(2D)nitride MXenes are predicted to exhibit exceptional metallic properties and high polarity;however,their synthesis remains challenging.Research has relied on traditional molten salt etching,highlight... Two-dimensional(2D)nitride MXenes are predicted to exhibit exceptional metallic properties and high polarity;however,their synthesis remains challenging.Research has relied on traditional molten salt etching,highlighting the need for a scalable,high-purity approach.Here,we present the first solution-based synthesis of Ti_(4)N_(3)T_(x)MXene via a novel saturated salt solution(S^(3))etching technique employing alkali metal salts.By optimizing the sintering process for high-purity Ti_(4)AlN_(3)MAX and refining the S^(3)etching route,we significantly reduced the etch pit density to 1.2×10^(6)cm^(-2)and lowered the etch pit formation rate to 4%,yielding high-quality,phasepure Ti_(4)N_(3)T_(x)MXene.Our study highlights the critical role of alkali metal ions in selective A-layer removal and demonstrates the impressive electrical conductivity and electromagnetic interference shielding performance of 2D nitride MXene,setting a new benchmark for this underexplored material.These findings pave the way for advancing 2D nitride MXenes and their diverse applications. 展开更多
关键词 Nitride MXene Nitride MAX precursor SINTERING Solution process saturated salt solution(S^(3))etching HIGH-PURITY Physical property
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A Recursive Method to Encryption-Decryption-Based Distributed Set-Membership Filtering for Time-Varying Saturated Systems Over Sensor Networks
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作者 Jun Hu Jiaxing Li +2 位作者 Chaoqing Jia Xiaojian Yi Hongjian Liu 《IEEE/CAA Journal of Automatica Sinica》 2025年第5期1047-1049,共3页
Dear Editor,This letter deals with the distributed recursive set-membership filtering(DRSMF)issue for state-saturated systems under encryption-decryption mechanism.To guarantee the data security,the encryption-decrypt... Dear Editor,This letter deals with the distributed recursive set-membership filtering(DRSMF)issue for state-saturated systems under encryption-decryption mechanism.To guarantee the data security,the encryption-decryption mechanism is considered in the signal transmission process.Specifically,a novel DRSMF scheme is developed such that,for both state saturation and encryption-decryption mechanism,the filtering error(FE)is limited to the ellipsoid domain.Then,the filtering error constraint matrix(FECM)is computed and a desirable filter gain is derived by minimizing the FECM.Besides,the bound-edness evaluation of the FECM is provided. 展开更多
关键词 time varying saturated systems signal transmission processspecificallya encryption decryption mechanism sensor networks recursive method distributed set membership filtering
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Distributed Saturated Impulsive Quasi-Consensus for Leader-Follower Multi-Agent Systems:An Open Topology Framework
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作者 Haitao Zhu Jianquan Lu +1 位作者 Yijun Lou Xinsong Yang 《IEEE/CAA Journal of Automatica Sinica》 2025年第9期1941-1943,共3页
Dear Editor,This letter studies a real-world issue in leader-follower multi-agent systems(MASs)named open topology,which permits the variations of agent set and network connections.Specially,a novel transition process... Dear Editor,This letter studies a real-world issue in leader-follower multi-agent systems(MASs)named open topology,which permits the variations of agent set and network connections.Specially,a novel transition process is developed to explain how the involved variation of network scale affects the dynamic behavior of the MASs.From a resource limited perspective,the distributed saturated impulsive control is then designed,under which some sufficient criteria are integrated into local quasi-consensus performance.We also provide a combined optimization algorithm for all agents to make the estimated domain of initial errors closer to the real one,thereby resulting in less conservativeness.Finally,a numerical example validates our results. 展开更多
关键词 distributed saturated impulsive control leader follower multi agent systems optimization algorithm agent set network open topology transition process open topologywhich quasi consensus
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Mechanical behavior and improved hypoplastic constitutive model for saturated frozen sand
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作者 ZhaoMing Yao XiangBin Fu Nan Li 《Research in Cold and Arid Regions》 2025年第4期195-204,共10页
The artificial ground-freezing method is the main technical means for the excavation of mines and tunnels through the water-rich sand layer,and the comprehensive understanding of the mechanical properties of frozen sa... The artificial ground-freezing method is the main technical means for the excavation of mines and tunnels through the water-rich sand layer,and the comprehensive understanding of the mechanical properties of frozen saturated sand and the stress-strain relationship under complex stress can provide important guidance.In this study,a series of true triaxial tests of frozen saturated sand samples were conducted.Combined with the test data,the effects of temperature and medium principal stress ratio(b)on the strength and deformation characteristics of frozen saturated sand are discussed.In addition,a cohesion tensor is introduced to the Wu-Lin hypoplastic model.A scalar value is used to characterize the effect of temperature on the strength of frozen soil.The defect that the original model cannot describe the tensile capacity of frozen soil under low stress conditions is clearly solved.In addition,the cumulative deformation state variable is introduced to improve the response performance of the model in triaxial compression tests.The hypoplastic model of frozen soil has shown good performance in simulating triaxial compression tests at different temperatures and medium principal stress ratios. 展开更多
关键词 saturated frozen sand True triaxial test Hypoplastic constitutive model Critical state
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Thermal mass transfer law and deformation properties of unsaturated sulfate saline soil
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作者 LIU Zhiyi SONG Yu +2 位作者 ZHOU Fengxi SUN Liepu GAO Fei 《Journal of Mountain Science》 2025年第6期2241-2260,共20页
The engineering diseases caused by seasonal sulfate saline soil in Hexi region of Gansu Province seriously affect the local infrastructure construction and operation maintenance.To address this issue,this study explor... The engineering diseases caused by seasonal sulfate saline soil in Hexi region of Gansu Province seriously affect the local infrastructure construction and operation maintenance.To address this issue,this study explored the thermal mass transfer law,pore fluid phase transition,soil deformation and microstructure of unsaturated sulfate saline soil under the open system.Firstly,based on the theories of porous media mechanics and continuum mechanics,combined with the conservation equations of mass,energy and momentum and considering the phase transition of pore fluid,a multi-field coupled mathematical model of hydro-thermal-salt-gasmechanical for unsaturated sulfate saline soil was established.Secondly,basic unknown variables such as pore water pressure,concentration,temperature,porosity,and displacement were selected to perform numerical simulation analysis on the equation system by“Comsol Multiphysics”finite element method.Finally,a comparative analysis was conducted between the on-site measured data and the numerical simulation results.The results show that the water and salt phase transitions caused by temperature change could lead to soil salt heave and frost heave,alter the pore structure of the soil,and reduce the compactness of the soil,ultimately being reflected in the changes in soil porosity.The influence of external temperature on soil temperature gradually decreases with increasing depth,and the sensitivity of frozen areas to external temperature is much higher than that of unfrozen areas.This study not only enriches the theoretical results of thermal mass transfer law and deformation of unsaturated sulfate saline soil,but also provides practical guidance for the prevention and control of engineering diseases in local sulfate saline soil. 展开更多
关键词 Unsaturated sulfate saline soil Thermal mass transfer Deformation properties Microstructure SATURATION
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Tracking spatial heterogeneity of local degree of saturation in unsaturated soils at different scales via X-ray computed tomography
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作者 Zhenliang Jiang Jianbin Liu Anthony Kwan Leung 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第6期3807-3818,共12页
Correctly tracking the evolution of spatial heterogeneity of local degree of saturation(Sr)in unsaturated soils is essential to explain the seepage phenomenon,which is crucial to assessing slope stability.Several meth... Correctly tracking the evolution of spatial heterogeneity of local degree of saturation(Sr)in unsaturated soils is essential to explain the seepage phenomenon,which is crucial to assessing slope stability.Several methods exist for quantifying the heterogeneity of local S_(r).However,a comprehensive comparison of these methods in terms of accuracy,relative advantages,and disadvantages is currently lacking.This paper presents a comparative analysis of local Sr obtained at multiple scales,ranging from the element scale to the slice,representative element volume(REV),pore,and voxel scales.The spatial heterogeneity of Sr in an unsaturated glass beads specimen at different matric suctions was visualised and quantified by multiscale X-ray micro-focus computed tomography image-based analysis methods.Local Sr obtained at different scales displayed a comparable trend along the sample depth,yet the REV-scale method showed a much scattered and discontinuous distribution.In contrast,the pore-scale method detected a distinct two-clustered,bimodal distribution of S_(r).The pore-scale method has the highest integrated resolution,as it has the highest spatial resolution(i.e.number of data points)and provides more information(i.e.number of extractable physical parameters).This method thus provides a more effective approach for tracking the spatial heterogeneity of S_(r).Based on this method,pore-scale water retention curves were determined,offering new quantitative means to characterise pore water heterogeneity and explainwater drainage processes such as hysteresis at the pore scale. 展开更多
关键词 Unsaturated soils Degree of saturation Computed tomography(CT)image-based analysis Multiscale Pore scale
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Strength characteristics of dry and saturated rock at different strain rates 被引量:33
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作者 周子龙 蔡鑫 +3 位作者 赵源 陈璐 熊成 李夕兵 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第7期1919-1925,共7页
The strength of rock materials is largely affected by water and loading conditions, but there are few studies on mechanical properties of saturated rocks at high strain rates. Through compressive tests on dry and satu... The strength of rock materials is largely affected by water and loading conditions, but there are few studies on mechanical properties of saturated rocks at high strain rates. Through compressive tests on dry and saturated sandstone specimens, it was found that the dynamic compressive strength of both dry and saturated sandstone specimens increased with the increase of strain rates. The saturated rock specimens showed stronger rate dependence than the dry ones. The water affecting factor (WAF), as the ratio of the strength under dry state to that under saturated state, was introduced to describe the influence of water on the compressive strength at different strain rates. The WAF under static load was close to 1.38, and decreased with the increase of strain rate. When the strain rate reached 190 s^-1, the WAF reduced to 0.98. It indicates that the compressive strength of saturated specimens can be higher than that of dry ones when the strain rate is high enough. Furthermore, the dual effects of water and strain rate on the strength of rock were discussed based on sliding crack model, which provided a good explanation for the experimental results. 展开更多
关键词 ROCK STRENGTH strain rate saturated rock
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Creep experiment and rheological model of deep saturated rock 被引量:13
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作者 刘浪 王革民 +1 位作者 陈建宏 杨珊 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第2期478-483,共6页
By the methods of uniaxial single-stage loading and graded incremental cyclic loading, the creep experiments were performed on the deep saturated rock from Dongguashan Mine, and the creep curves of saturated rock unde... By the methods of uniaxial single-stage loading and graded incremental cyclic loading, the creep experiments were performed on the deep saturated rock from Dongguashan Mine, and the creep curves of saturated rock under different loading stresses were obtained. By comparing with the creep rule of dry rock in the same location, the creep rule of deep saturated rock was analyzed. Based on the united rheological mechanical model, the rheological model of deep saturated rock was recognized, and the parameters of the model were determined. The results show that the creep curves are very smooth under low stress, but the phenomena of wave and catastrophe turn up under high stress, and the bearing capacity of rock is weakening over time. The rheological properties of saturated and dry rocks are very different under tlie condition of deep high stress, especially when unloading, degradation and damage of rock quality is more serious, and the effect of water cannot be neglected. The H--HIN--NJS model (Schofield-Scott-Blair model) was selected to represent the rheology rule of deep saturated rock, and the fitting curves of model agree well with the experiment data, so the selected model is reasonable. 展开更多
关键词 deep saturated rock CREEP united rheological model rheology rule
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Distinctive roles of unsaturated and saturated fatty acids in hyperlipidemic pancreatitis 被引量:32
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作者 Yu-Ting Chang Ming-Chu Chang +2 位作者 Chien-Chih Tung Shu-Chen Wei Jau-Min Wong 《World Journal of Gastroenterology》 SCIE CAS 2015年第32期9534-9543,共10页
AIM: To investigate how the saturated and unsaturated fatty acid composition influences the susceptibility of developing acute pancreatitis. METHODS: Primary pancreatic acinar cells were treated with low and high conc... AIM: To investigate how the saturated and unsaturated fatty acid composition influences the susceptibility of developing acute pancreatitis. METHODS: Primary pancreatic acinar cells were treated with low and high concentrations of different saturated and unsaturated fatty acids, and changes in the cytosolic Ca2+ signal and the expression of protein kinase C(PKC) were measured after treatment. RESULTS: Unsaturated fatty acids at high concentrations, including oleic acid, linoleic acid, palmitoleic acid, docosahexaenoic acid, and arachidonic acid, induced a persistent rise in cytosolic Ca2+ concentrations in acinar cells. Unsaturated fatty acids at low concentrations and saturated fatty acids, including palmitic acid, stearic acid, and triglycerides, at low and high concentrations were unable to induce a rise in Ca2+ concentrations in acinar cells. Unsaturated fatty acids at high concentrations but not saturated fatty acids induced intra-acinar cell trypsin activation and cell damage and increased PKC expression.CONCLUSION: At sufficiently high concentrations, unsaturated fatty acids were able to induce acinar cells injury and promote the development of pancreatitis. Unsaturated fatty acids may play a distinctive role in the pathogenesis of pancreatitis through the activation of PKC family members. 展开更多
关键词 UNsaturated FATTY ACID saturated FATTY ACID Hypert
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Dietary saturated fatty acid and polyunsaturated fatty acid oppositely affect hepatic NOD-like receptor protein 3 inflammasome through regulating nuclear factor-kappa B activation 被引量:12
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作者 Yong-heng Sui Wen-jing Luo +1 位作者 Qin-Yu Xu jing hua 《World Journal of Gastroenterology》 SCIE CAS 2016年第8期2533-2544,共12页
AIM: To investigate the effect of different dietary fatty acids on hepatic inflammasome activation.METHODS: Wild-type C57BL/6 mice were fed either a high-fat diet or polyunsaturated fatty acid (PUFA)-enriched diet. Pr... AIM: To investigate the effect of different dietary fatty acids on hepatic inflammasome activation.METHODS: Wild-type C57BL/6 mice were fed either a high-fat diet or polyunsaturated fatty acid (PUFA)-enriched diet. Primary hepatocytes were treated with either saturated fatty acids (SFAs) or PUFAs as well as combined with lipopolysaccharide (LPS). The expression of NOD-like receptor protein 3 (NLRP3) inflammasome, peroxisome proliferator-activated receptor-&#x003b3; and nuclear factor-kappa B (NF-&#x003ba;B) was determined by real-time PCR and Western blot. The activity of Caspase-1 and interleukine-1&#x003b2; production were measured.RESULTS: High-fat diet-induced hepatic steatosis was sufficient to induce and activate hepatic NLRP3 inflammasome. SFA palmitic acid (PA) directly activated NLRP3 inflammasome and increased sensitization to LPS-induced inflammasome activation in hepatocytes. In contrast, PUFA docosahexaenoic acid (DHA) had the potential to inhibit NLRP3 inflammasome expression in hepatocytes and partly abolished LPS-induced NLRP3 inflammasome activation. Furthermore, a high-fat diet increased but PUFA-enriched diet decreased sensitization to LPS-induced hepatic NLRP3 inflammasome activation in vivo. Moreover, PA increased but DHA decreased phosphorylated NF-&#x003ba;B p65 protein expression in hepatocytes.CONCLUSION: Hepatic NLRP3 inflammasome activation played an important role in the development of non-alcoholic fatty liver disease. Dietary SFAs and PUFAs oppositely regulated the activity of NLRP3 inflammasome through direct activation or inhibition of NF-&#x003ba;B. 展开更多
关键词 Non-alcoholic fatty liver disease NOD-like receptor protein 3 inflammasome saturated fatty acids Polyunsaturated fatty acids Nuclear factor-kappa B
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Effects of microalgal polyunsaturated fatty acid oil on body weight and lipid accumulation in the liver of C57BL/6 mice fed a high fat diet 被引量:2
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作者 Ryeo-Eun Go Kyung-A Hwang +7 位作者 Geon-Tae Park Hae-Miru Lee Geum-A Lee Cho-Won Kim So-Ye Jeon Jeong-Woo Seo Won-Kyung Hong Kyung-Chul Choi 《The Journal of Biomedical Research》 CAS CSCD 2016年第3期234-242,共9页
Dietary polyunsaturated fatty acids (PUFAs), which are abundant in marine fish oils, have recently received global attention for their prominent anti-obesogenic effects. Among PUFAs, eicosapentaenoic acid (EPA; 20... Dietary polyunsaturated fatty acids (PUFAs), which are abundant in marine fish oils, have recently received global attention for their prominent anti-obesogenic effects. Among PUFAs, eicosapentaenoic acid (EPA; 20:5n-3) and docosahexaenoic acid (DHA; 22:6n-3), which are n-3 long-chain PUFAs widely referred to as omega-3 oils, were reported to prevent the development of obesity in rodents and humans. In the present study, we evaluated the anti-obesity effects of microalgal oil on high-fat induced obese C57BL/6 mice, compared with commercial omega-3 fish oil and vegetable corn oil. Microalgal oil is an inherent mixture of several PUFAs, including EPA, DHA and other fatty acids produced from a marine microalgal strain of Thraustochytriidae sp. derived mutant. It was found to contain more PUFAs (〉80%) and more omega-3 oils than commercial omega-3 fish oil (PUFAs 〉31%) and corn oil (PUFAs 59%). All three types of oils induced weight loss in high-fat-induced obese mice, with the loss induced by microalgal oil being most significant at 9 weeks (10% reduction). However, the oils tested did not improve blood lipid levels, although microalgal oil showed an apparent inhibitory effect on lipid accumulation in the liver. These findings may be attributed to the higher PUFA content, including omega-3 oils of microalgal oil than other oils. Collectively, these findings suggest that microalgal oil, derived from Thraustochytriidae sp. derived mutant, is a prominent candidate for replacement of omega-3 fish oils based on its apparent anti-obesity effect in vivo. 展开更多
关键词 ANTI-OBESITY polyunsaturated fatty acid saturated fatty acid omega-3 oil MICROALGAE
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