Narrow backfill earth pressure estimation is applied to study the stability of supporting structures in the vicinity of existing buildings.Previous narrow backfill earth pressure studies have neglected seismic-unsatur...Narrow backfill earth pressure estimation is applied to study the stability of supporting structures in the vicinity of existing buildings.Previous narrow backfill earth pressure studies have neglected seismic-unsaturated seepage multi-field coupling,resulting in inaccurate estimates.To address these deficiencies,this paper proposed a calculation method for seismic passive earth pressure in unsaturated narrow backfill,based on inclined thin-layer units.It considers the interlayer shear stress,arching effect,and the multi-field coupling of seismic-unsaturated seepage.Additionally,this paper includes a parametric sensitivity analysis.The outcomes indicate that the earthquake passive ground pressure of unsaturated narrow backfill can be reduced by increasing the aspect ratio,seismic acceleration coefficient,and unsaturation parameterα.It can also be reduced by decreasing the effective interior friction angle,soil cohesion,wallearth friction angle,and vertical discharge.Furthermore,for any width soil,lowering the elevation of the action point of passive thrust can be attained by raising the effective interior friction angle,wall-earth friction angle,and unsaturation parameterα.Reducing soil cohesion,seismic acceleration coefficient,and vertical discharge can also lower the height of the application point of passive thrust.展开更多
Recent advancements have led to the synthesis of various new metal-containing explosives,particularly energetic metal-organic frameworks(EMOFs),which feature high-energy ligands within well-ordered crystalline structu...Recent advancements have led to the synthesis of various new metal-containing explosives,particularly energetic metal-organic frameworks(EMOFs),which feature high-energy ligands within well-ordered crystalline structures.These explosives exhibit significant advantages over traditional compounds,including higher density,greater heats of detonation,improved mechanical hardness,and excellent thermal stability.To effectively evaluate their detonation performance,it is crucial to have a reliable method for predicting detonation heat,velocity,and pressure.This study leverages experimental data and outputs from the leading commercial computer code to identify suitable decomposition pathways for different metal oxides,facilitating straightforward calculations for the detonation performance of alkali metal salts,and metal coordination compounds,along with EMOFs.The new model enhances predictive reliability for detonation velocities,aligning more closely with experimental results,as evi-denced by a root mean square error(RMSE)of 0.68 km/s compared to 1.12 km/s for existing methods.Furthermore,it accommodates a broader range of compounds,including those containing Sr,Cd,and Ag,and provides predictions for EMOFs that are more consistent with computer code outputs than previous predictive models.展开更多
A recently published modeling approach for the penetration into adobe and previous approaches implicitly criticized are reviewed and discussed.This article contains a note on the paper titled“Ballistic model for the ...A recently published modeling approach for the penetration into adobe and previous approaches implicitly criticized are reviewed and discussed.This article contains a note on the paper titled“Ballistic model for the prediction of penetration depth and residual velocity in adobe:A new interpretation of the ballistic resistance of earthen masonry”(DOI:https://doi.org/10.1016/j.dt.2018.07.017).Reply to the Note from Li Piani et al is linked to this article.展开更多
大数据技术在地球科学中的应用已成为国家战略重点,《“十四五”大数据产业发展规划》等政策为多源异构数据整合提供了支撑。大语言模型(LLM)是一种基于深度学习技术的人工智能模型。然而,通用大语言模型(如GPT-4、Deepseek-R1)在专业...大数据技术在地球科学中的应用已成为国家战略重点,《“十四五”大数据产业发展规划》等政策为多源异构数据整合提供了支撑。大语言模型(LLM)是一种基于深度学习技术的人工智能模型。然而,通用大语言模型(如GPT-4、Deepseek-R1)在专业领域存在局限性,因训练语料缺乏地球科学细分知识,导致回答笼统或错误(即“幻觉”)(Singhal et al.,2025),Zhou Zhi等(2024)在医疗领域通过Med-PaLM2构建垂直知识库,He Yong等(2024)法律领域基于LawGPT实现法规精准检索。在地球科学领域尚未形成系统的本地化知识问答方案。展开更多
With the growing awareness of environmental protection and the increasing demand for rare earth elements(REEs),it has become necessary to efficiently remove and recover REEs from mine wastewater.In this study,jarosite...With the growing awareness of environmental protection and the increasing demand for rare earth elements(REEs),it has become necessary to efficiently remove and recover REEs from mine wastewater.In this study,jarosite(Jar)and schwertmannite(Sch)were biosynthesized using Acidithiobacillus ferrooxidans for the adsorption of REEs.Additionally,the adsorption capacities of Jar and Sch for La^(3+),Ce^(3+),Pr^(3+),Nd^(3+),Sm^(3+),Gd^(3+),Dy^(3+),and Y^(3+)in mine wastewater were improved by mechanical activation.XRD,FTIR,BET,and SEM-EDS analyses revealed that mechanical activation did not alter the phase of the material,but increased the amount of surface-OH and SO42−groups,as well as the specific surface area.This significantly enhanced the adsorption performance of Jar and Sch for REEs.The optimum adsorption time and pH were determined through batch adsorption experiments.Besides,the adsorption kinetics were studied and found to align well with the pseudo-second-order model.Furthermore,the thermodynamic parameters(ΔG^(Θ),ΔH^(Θ)andΔS^(Θ))and adsorption isotherms were analyzed.The results indicated that mechanically activated schwertmannite(M-Sch)exhibited superior adsorption performance for REEs compared to mechanically activated jarosite(M-Jar).Moreover,M-Sch was reusable and exhibited high adsorption efficiency of REEs in actual mine wastewater,exceeding 92%.展开更多
Because of an unfortunate mistake by authors,the Project(5227010679)of Foundation item was wrong.The corrected Project is shown as follows:Project(52271073).
In low Earth orbit(LEO)satellite networks,on-board energy resources of each satellite are extremely limited.And with the increase of the node number and the traffic transmis-sion pressure,the energy consumption in the...In low Earth orbit(LEO)satellite networks,on-board energy resources of each satellite are extremely limited.And with the increase of the node number and the traffic transmis-sion pressure,the energy consumption in the networks presents uneven distribution.To achieve energy balance in networks,an energy consumption balancing optimization algorithm of LEO networks based on distance energy factor(DEF)is proposed.The DEF is defined as the function of the inter-satellite link dis-tance and the cumulative network energy consumption ratio.According to the minimum sum of DEF on inter-satellite links,an energy consumption balancing algorithm based on DEF is pro-posed,which can realize dynamic traffic transmission optimiza-tion of multiple traffic services.It can effectively reduce the energy consumption pressure of core nodes with high energy consumption in the network,make full use of idle nodes with low energy consumption,and optimize the energy consumption dis-tribution of the whole network according to the continuous itera-tions of each traffic service flow.Simulation results show that,compared with the traditional shortest path algorithm,the pro-posed method can improve the balancing performance of nodes by 75%under certain traffic pressure,and realize the optimiza-tion of energy consumption balancing of the whole network.展开更多
Human beings are now facing global and regional sustainable development challenges.In China, Earth observation data play a fundamental role in Earth system science research. The support given by Earth observation data...Human beings are now facing global and regional sustainable development challenges.In China, Earth observation data play a fundamental role in Earth system science research. The support given by Earth observation data is required by many studies, including those on Earth's limited natural resources, the rapid development of economic and social needs, global change, extreme events, food security, water resources, sustainable economic and urban development, and emergency response. Application operation systems in many ministries and departments in China have entered a stage of sustainable development, and the State Key Project of High-Resolution Earth Observation Systems has been progressing since 2006. Earth observation technology in China has entered a period of rapid development.展开更多
A method, doping WC with La(NO 3) 3, of producing cemented carbide with rare earth was introduced. The effects of lanthanum on the mechanical properties and microstructure of WC 9(Co 75%Ni) cemented carbide were studi...A method, doping WC with La(NO 3) 3, of producing cemented carbide with rare earth was introduced. The effects of lanthanum on the mechanical properties and microstructure of WC 9(Co 75%Ni) cemented carbide were studied and a rock drilling experiment was carried out.The experimental results show that both transverse rupture strength (TRS) and hardness of WC 9(Co 75%Ni) rare earth cemented carbides can match that of WC 9Co cemented carbide, when La 2O 3 / (Co+Ni) ratio is 0.3%, the abnormal growth of WC grain in the cemented carbide can be restrained effectively, the homogeneity of grain size in microstructure and the wear resistance are improved, which can be matchable to that of WC 9Co cemented carbide for mining.展开更多
Rare earth element （REE） concentrations were measured by ICP-MS for groundwater collected from deep seated Taiyuan Fm limestone aquifer （from -400 to -530 m） in Renlou Coal Mine, northern Anhui Province, China. It...Rare earth element （REE） concentrations were measured by ICP-MS for groundwater collected from deep seated Taiyuan Fm limestone aquifer （from -400 to -530 m） in Renlou Coal Mine, northern Anhui Province, China. It can be concluded that the groundwater is warm （34.0-37.2 ℃） C1-Ca, Na type water with circum-neutral pH （7.35-8.28） and high total dissolved solids （TDS, 1 746-2 849 mg/L）. The groundwater exhibits heavy REEs enrichment relative to light REEs compared with Post Archean Average Shale （PAAS）, as well as their aquifer rocks （limestone）. The enrichment of REEs is considered to be controlled by terrigeneous materials （e.g. zircon） in aquifer rocks, whereas the fractionation of REEs is controlled by marine derived materials （e.g. calcite）, to a less extent, terrigeneous materials and inorganic complexation. The Ce anomalies normalized to PAAS and aquifer rocks are weak, which probably reflects the signature of the aquifer rock rather than redox conditions or pH. The similarities of REE patterns between groundwater and aquifer rocks imply that aquifer rocks play important roles in controlling the REE characteristics of groundwater, and then provide a probability for discrimination of groundwater sources by using REEs.展开更多
基金Project(42277175)supported by the National Natural Science Foundation of ChinaProject(NRMSSHR-2022-Z08)supported by the Key Laboratory of Natural Resources Monitoring and Supervision in Southern Hilly Region,Ministry of Natural Resources,China。
文摘Narrow backfill earth pressure estimation is applied to study the stability of supporting structures in the vicinity of existing buildings.Previous narrow backfill earth pressure studies have neglected seismic-unsaturated seepage multi-field coupling,resulting in inaccurate estimates.To address these deficiencies,this paper proposed a calculation method for seismic passive earth pressure in unsaturated narrow backfill,based on inclined thin-layer units.It considers the interlayer shear stress,arching effect,and the multi-field coupling of seismic-unsaturated seepage.Additionally,this paper includes a parametric sensitivity analysis.The outcomes indicate that the earthquake passive ground pressure of unsaturated narrow backfill can be reduced by increasing the aspect ratio,seismic acceleration coefficient,and unsaturation parameterα.It can also be reduced by decreasing the effective interior friction angle,soil cohesion,wallearth friction angle,and vertical discharge.Furthermore,for any width soil,lowering the elevation of the action point of passive thrust can be attained by raising the effective interior friction angle,wall-earth friction angle,and unsaturation parameterα.Reducing soil cohesion,seismic acceleration coefficient,and vertical discharge can also lower the height of the application point of passive thrust.
基金the research committee at Malek Ashtar University of Technology (MUT) for their invaluable support of this project
文摘Recent advancements have led to the synthesis of various new metal-containing explosives,particularly energetic metal-organic frameworks(EMOFs),which feature high-energy ligands within well-ordered crystalline structures.These explosives exhibit significant advantages over traditional compounds,including higher density,greater heats of detonation,improved mechanical hardness,and excellent thermal stability.To effectively evaluate their detonation performance,it is crucial to have a reliable method for predicting detonation heat,velocity,and pressure.This study leverages experimental data and outputs from the leading commercial computer code to identify suitable decomposition pathways for different metal oxides,facilitating straightforward calculations for the detonation performance of alkali metal salts,and metal coordination compounds,along with EMOFs.The new model enhances predictive reliability for detonation velocities,aligning more closely with experimental results,as evi-denced by a root mean square error(RMSE)of 0.68 km/s compared to 1.12 km/s for existing methods.Furthermore,it accommodates a broader range of compounds,including those containing Sr,Cd,and Ag,and provides predictions for EMOFs that are more consistent with computer code outputs than previous predictive models.
文摘A recently published modeling approach for the penetration into adobe and previous approaches implicitly criticized are reviewed and discussed.This article contains a note on the paper titled“Ballistic model for the prediction of penetration depth and residual velocity in adobe:A new interpretation of the ballistic resistance of earthen masonry”(DOI:https://doi.org/10.1016/j.dt.2018.07.017).Reply to the Note from Li Piani et al is linked to this article.
文摘大数据技术在地球科学中的应用已成为国家战略重点,《“十四五”大数据产业发展规划》等政策为多源异构数据整合提供了支撑。大语言模型(LLM)是一种基于深度学习技术的人工智能模型。然而,通用大语言模型(如GPT-4、Deepseek-R1)在专业领域存在局限性,因训练语料缺乏地球科学细分知识,导致回答笼统或错误(即“幻觉”)(Singhal et al.,2025),Zhou Zhi等(2024)在医疗领域通过Med-PaLM2构建垂直知识库,He Yong等(2024)法律领域基于LawGPT实现法规精准检索。在地球科学领域尚未形成系统的本地化知识问答方案。
基金Project(2022YFC2105300) supported by the National Key Research and Development Program of ChinaProject(52274288) supported by the National Natural Science Foundation of China。
文摘With the growing awareness of environmental protection and the increasing demand for rare earth elements(REEs),it has become necessary to efficiently remove and recover REEs from mine wastewater.In this study,jarosite(Jar)and schwertmannite(Sch)were biosynthesized using Acidithiobacillus ferrooxidans for the adsorption of REEs.Additionally,the adsorption capacities of Jar and Sch for La^(3+),Ce^(3+),Pr^(3+),Nd^(3+),Sm^(3+),Gd^(3+),Dy^(3+),and Y^(3+)in mine wastewater were improved by mechanical activation.XRD,FTIR,BET,and SEM-EDS analyses revealed that mechanical activation did not alter the phase of the material,but increased the amount of surface-OH and SO42−groups,as well as the specific surface area.This significantly enhanced the adsorption performance of Jar and Sch for REEs.The optimum adsorption time and pH were determined through batch adsorption experiments.Besides,the adsorption kinetics were studied and found to align well with the pseudo-second-order model.Furthermore,the thermodynamic parameters(ΔG^(Θ),ΔH^(Θ)andΔS^(Θ))and adsorption isotherms were analyzed.The results indicated that mechanically activated schwertmannite(M-Sch)exhibited superior adsorption performance for REEs compared to mechanically activated jarosite(M-Jar).Moreover,M-Sch was reusable and exhibited high adsorption efficiency of REEs in actual mine wastewater,exceeding 92%.
文摘Because of an unfortunate mistake by authors,the Project(5227010679)of Foundation item was wrong.The corrected Project is shown as follows:Project(52271073).
基金supported by the National Key Research and Development Program(2021YFB2900604).
文摘In low Earth orbit(LEO)satellite networks,on-board energy resources of each satellite are extremely limited.And with the increase of the node number and the traffic transmis-sion pressure,the energy consumption in the networks presents uneven distribution.To achieve energy balance in networks,an energy consumption balancing optimization algorithm of LEO networks based on distance energy factor(DEF)is proposed.The DEF is defined as the function of the inter-satellite link dis-tance and the cumulative network energy consumption ratio.According to the minimum sum of DEF on inter-satellite links,an energy consumption balancing algorithm based on DEF is pro-posed,which can realize dynamic traffic transmission optimiza-tion of multiple traffic services.It can effectively reduce the energy consumption pressure of core nodes with high energy consumption in the network,make full use of idle nodes with low energy consumption,and optimize the energy consumption dis-tribution of the whole network according to the continuous itera-tions of each traffic service flow.Simulation results show that,compared with the traditional shortest path algorithm,the pro-posed method can improve the balancing performance of nodes by 75%under certain traffic pressure,and realize the optimiza-tion of energy consumption balancing of the whole network.
文摘Human beings are now facing global and regional sustainable development challenges.In China, Earth observation data play a fundamental role in Earth system science research. The support given by Earth observation data is required by many studies, including those on Earth's limited natural resources, the rapid development of economic and social needs, global change, extreme events, food security, water resources, sustainable economic and urban development, and emergency response. Application operation systems in many ministries and departments in China have entered a stage of sustainable development, and the State Key Project of High-Resolution Earth Observation Systems has been progressing since 2006. Earth observation technology in China has entered a period of rapid development.
文摘A method, doping WC with La(NO 3) 3, of producing cemented carbide with rare earth was introduced. The effects of lanthanum on the mechanical properties and microstructure of WC 9(Co 75%Ni) cemented carbide were studied and a rock drilling experiment was carried out.The experimental results show that both transverse rupture strength (TRS) and hardness of WC 9(Co 75%Ni) rare earth cemented carbides can match that of WC 9Co cemented carbide, when La 2O 3 / (Co+Ni) ratio is 0.3%, the abnormal growth of WC grain in the cemented carbide can be restrained effectively, the homogeneity of grain size in microstructure and the wear resistance are improved, which can be matchable to that of WC 9Co cemented carbide for mining.
基金Project(40873015) supported by the National Natural Science Foundation of ChinaProject(08010302062) supported by the Eleventh Five-year Scientific and Technological Program of Anhui Province,China
文摘Rare earth element （REE） concentrations were measured by ICP-MS for groundwater collected from deep seated Taiyuan Fm limestone aquifer （from -400 to -530 m） in Renlou Coal Mine, northern Anhui Province, China. It can be concluded that the groundwater is warm （34.0-37.2 ℃） C1-Ca, Na type water with circum-neutral pH （7.35-8.28） and high total dissolved solids （TDS, 1 746-2 849 mg/L）. The groundwater exhibits heavy REEs enrichment relative to light REEs compared with Post Archean Average Shale （PAAS）, as well as their aquifer rocks （limestone）. The enrichment of REEs is considered to be controlled by terrigeneous materials （e.g. zircon） in aquifer rocks, whereas the fractionation of REEs is controlled by marine derived materials （e.g. calcite）, to a less extent, terrigeneous materials and inorganic complexation. The Ce anomalies normalized to PAAS and aquifer rocks are weak, which probably reflects the signature of the aquifer rock rather than redox conditions or pH. The similarities of REE patterns between groundwater and aquifer rocks imply that aquifer rocks play important roles in controlling the REE characteristics of groundwater, and then provide a probability for discrimination of groundwater sources by using REEs.
