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Dissolution and Deformation Characteristics of Limestones Containing Different Calcite and Dolomite Content Induced by CO_(2)-Water-Rock Interaction
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作者 CHEN Bowen LI Qi +1 位作者 TAN Yongsheng Ishrat Hameed ALVI 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2023年第3期956-971,共16页
To investigate the impacts of mineral composition on physical and mechanical properties of carbonate rocks,limestone specimens containing different contents in calcite and dolomite are selected to perform CO_(2)-water... To investigate the impacts of mineral composition on physical and mechanical properties of carbonate rocks,limestone specimens containing different contents in calcite and dolomite are selected to perform CO_(2)-water-rock reaction experiments.The X-ray Diffraction(XRD) and Nuclear Magnetic Resonance(NMR) are carried out to examine the change characteristics of mineral dissolution and pore structure after reaction.The core flooding experiments with Fiber Bragg gratings are implemented to examine the stress sensitivity of carbonate rocks.The results show that the limestones containing pure calcite are more susceptible to acid dissolution compared to limestone containing impure dolomite.The calcite content in pure limestone decreases as the reaction undergoes.The dissolution of dolomite leads to the formation of calcite in impure limestone.Calcite dissolution leads to the formation of macropore and flow channels in pure limestone,while the effects of impure dolomite in impure limestone results in mesopore formation.When confining pressure is lower than 12 MPa,pure limestones demonstrate higher strain sensitivity coefficients compared to impure limestone containing dolomite after reaction.When confining pressure exceeds 12 MPa,the strain sensitivity coefficients of both pure and impure limestones become almost equal. 展开更多
关键词 CO_(2) geological storage carbonate rocks CO_(2)-water-rock interaction deformation response Fiber Bragg gratings sensors
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Groundwater monitoring of an open-pit limestone quarry:Water-rock interaction and mixing estimation within the rock layers by geochemical and statistical analyses 被引量:9
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作者 Khy Eam Eang Toshifumi Igarashi +3 位作者 Megumi Kondo Tsurugi Nakatani Carlito Baltazar Tabelin Ryota Fujinaga 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2018年第6期849-857,共9页
Water-rock interaction and groundwater mixing are important phenomena in understanding hydrogeological systems and the stability of rock slopes especially those consisting largely of moderately watersoluble minerals l... Water-rock interaction and groundwater mixing are important phenomena in understanding hydrogeological systems and the stability of rock slopes especially those consisting largely of moderately watersoluble minerals like calcite. In this study, the hydrogeological and geochemical evolutions of groundwater in a limestone quarry composed of three strata: limestone layer(covering), interbedded layer under the covering layer, and slaty greenstone layer(basement) were investigated. Water-rock interaction in the open-pit limestone quarry was evaluated using PHREEQC, while hierarchical cluster analysis(HCA)and principal component analysis(PCA) were used to classify and identify water sources responsible for possible groundwater mixing within rock layers. In addition, Geochemist's Workbench was applied to estimate the mixing fractions to clarify sensitive zones that may affect rock slope stability. The results showed that the changes in Ca2+and HCO3àconcentrations of several groundwater samples along the interbedded layer could be attributed to mixing groundwater from the limestone layer and that from slaty greenstone layer. Based on the HCA and PCA results, groundwaters were classified into several types depending on their origin:(1) groundwater from the limestone layer(LO),(2) mixed groundwater flowing along the interbedded layer(e.g., groundwater samples L-7, L-11, S-3 and S-4), and(3) groundwater originating from the slaty greenstone layer(SO). The mixing fractions of 41% LO: 59% SO, 64% LO: 36% SO, 43%LO: 57% SOand 25% LO: 75% SOon the normal days corresponded to groundwaters L-7, L-11, S-3 and S-4,respectively, while the mixing fractions of groundwaters L-7 and L-11(61% LO: 39% SOand 93% LO: 7% SO,respectively) on rainy days became the majority of groundwater originating from the limestone layer.These indicate that groundwater along the interbedded layer significantly affected the stability of rock slopes by enlarging multi-breaking zones in the layer through calcite dissolution and inducing high water pressure, tension cracks and potential sliding plane along this layer particularly during intense rainfall episodes. 展开更多
关键词 water-rock interaction GROUNDWATER MIXING Interbedded layer Geochemist’s WORKBENCH ROCK SLOPE stability
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Experiment study on water-rock interaction about gold activation and migration in different solutions 被引量:2
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作者 DAI Ta gen, GU Li, QIU Dong sheng, XIE Wen bing (College of Resources, Environment and Civil Engineering, Central South University, Changsha 410083, China) 《Journal of Central South University of Technology》 2001年第2期105-107,共3页
The interactions on gold active and migratory quantities and rates between tuffaceous slate and solu tions with different compositions were experimentally studied at 200 ℃, 20 MPa, in a high pressure apparatus. After... The interactions on gold active and migratory quantities and rates between tuffaceous slate and solu tions with different compositions were experimentally studied at 200 ℃, 20 MPa, in a high pressure apparatus. After reaction, tuffaceous slate became light colored and soft, and its mass density reduced. The amount of gold extracted from tuffaceous slate ranges widely, from 0 027 to 0 234 μg/g. Chlorine solution may activate appreciable amount of gold, and the gold migratory rate is high enough, from 50 70% to 92 30%, which reveals that sulphur and chlorine work together in solutions to accelerate gold activation and migration, and to realize gold mineralization in favorable places. 展开更多
关键词 water rock interaction ACTIVATION MIGRATION CHLORINE SULPHUR GOLD
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Hydrogen and Oxygen Isotope Study on the Water-Rock Interaction of the Yinshan (Cu-) Pb-Zn-Ag Ore Deposit, Jiangxi Province 被引量:1
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作者 Zhang Ligang, Liu Jingxiu, Yu Guixiang and Chen Zhensheng Yichang Institute of Geology and Mineral Resources, CAGS, Yichang, Hubei Jiang Minxi 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1996年第3期274-289,共16页
The δ18O values of vein quartz of different stages from the Yinshan ore deposit are constant around 16‰ and the calculated δ18OH2O values attain 8‰± ; the δDH2O values of fluid inclu-sions in vein quartz are... The δ18O values of vein quartz of different stages from the Yinshan ore deposit are constant around 16‰ and the calculated δ18OH2O values attain 8‰± ; the δDH2O values of fluid inclu-sions in vein quartz are constant at about-60‰. From the surface down to 1200 m below the δ18O values of altered rocks gradually decrease from 15‰± to 11‰± . Various water-rock inversion calculations indicate that the ore fluids were formed by the interaction between meteoric water and phyllite at 350℃ and the effective W/ R value of around 0.1. When the water-rock exchange in the upper mineralization system took place, the effective W / R value increased to 5.0 or more. As a result, an evolution and mineralization model of a buffered open system with two-stage water-rock interactions is proposed in this study. 展开更多
关键词 H and O isotopes water-rock exchange buffered open system Yinshan of Jiangxi Province
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GIS-Hydrogeochemical Model of the YaoundéFractured Rock Aquifer, Cameroon: Aquifer Setting, Seasonal Variations in Groundwater-Rock Interaction and Water Quality
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作者 Richard Ayuk II Akoachere Omabgemi Omoloju Yaya +3 位作者 Sonia Ebot Egbe Thomson Areakpoh Eyong Bihmimihney Nelly Nji Diana Besem Tambe 《Journal of Geoscience and Environment Protection》 2019年第5期232-263,共32页
This study of the gneiss-fractured-rock aquifer in Yaoundé capital of Cameroon determines: the aquifer setting-flow systems, the aquifer type, seasonal variations in rock-water interactions, evolution of the hydr... This study of the gneiss-fractured-rock aquifer in Yaoundé capital of Cameroon determines: the aquifer setting-flow systems, the aquifer type, seasonal variations in rock-water interactions, evolution of the hydrogeochemical processes, physicochemical parameters and the suitability for domestic-agro-industrial use of the groundwater. Physicochemical field tests were carried out on 445 wells during four seasons for EC, pH, TDS, Temperature and static water level from July 2016 to May 2017. 90 well samples were analyzed 45 samples per season: wet/dry. 38 borewell logs were used together with structural data to determine the aquifer setting. The field physico-chemical and laboratory analysis data of well samples were mounted unto various GIS software platforms: Global mapper, AqQa, Aquachem, Rockworks, Logplot7, Surfer and ArcGIS, to get indices/parameters/figures, by use of Durov’s, Piper’s and Gibbs diagrams, Water quality index WQI, USSL ratio, Sodium Absorption ratio SAR, Percent sodium %Na, Kelly Ratio KR, Magnesium Absorption Ratio MAR, Total Hardness TH, Residual Sodium Carbonate RSC and Permeability Index PI that were determined. The process of groundwater ions acquisition is three-fold: by recharge through atmospheric precipitation, by ion exchange/simple dissolution between the rock-groundwater and by groundwater mixing in its flow path. Water types are Ca-HCO3, Mg-HCO3 and Mg-Cl while hydrogeochemical facies are Ca-Mg-HCO3 and Ca-Mg-Cl-SO4. Most water samples are fresh, potable and soft all seasons. The hydrogeological conceptual model is that of a three-layered single phreatic fractured-rock-aquifer while other researchers postulated a two-aquifer, phreatic and semi-confined, two-layered model. 展开更多
关键词 GIS-Hydrogeochemical Model Groundwater-rock interaction Fractured Rock AQUIFER AQUIFER SETTING Water Quality Yaoundé Cameroon
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Water-Rock Interaction in Tarim Basin: Constraints from Oilfield Water Geochemistry 被引量:3
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作者 蔡春芳 梅博文 +1 位作者 李伟 曾凡刚 《Chinese Journal Of Geochemistry》 EI CAS 1997年第4期289-303,共15页
Oilfield waters from Cenozoic and Mesozoic terrestrial and Paleozoic marine environments in the Tarim Basin show no obvious difference in water chemistry except Br and isotopic compositions. The Paleozoic marine strat... Oilfield waters from Cenozoic and Mesozoic terrestrial and Paleozoic marine environments in the Tarim Basin show no obvious difference in water chemistry except Br and isotopic compositions. The Paleozoic marine strata have higher Br concentrations than the terrestrial sediments, and the lack of obvious relationship between Br and Ⅰ suggests that Br is not, for the most part, derived from the degradation of organic matter. The oilfield waters are characterized by high TDS (total dissolved solids), ranging from 120000mg/L to 320000mg/L,relatively low Mg, high Ca, Sr, and CF relative to Br of evaporating seawater, suggestive of enhanced water-rock interaction. (Al (organic acid anions) concentrations are generally lower than 1500 mg/L with high values occurring over the temperature range from 95℃ to 140℃ ,in the Cambrian to Jurassic systems, and nearby unconformities. Organic acids are considered to be generated mainly from thermal maturation of kerogens during progressive burial of the Jurassic-Triassic and Cambrian-Ordovician systems, biodegradation of crude oils nearby unconformities, and thermochemical sulfate reduction in part of the Cambrian and Ordovician strata.High Al concentrations up to 3 mg/L to 5. 5 mg/L tend to occur in the waters of high OAA or petroleum- bearing intervals, suggesting the presence of organic complexing agents. Calculation by SOLMINEQ. 88 with updated database shows that AlAc2+ may account for more than 30%of the total Al. IsotoPic measurements (δD, δ18O) provide evidence for the following types of waters: diagenetically- modified connate meteoric water from the Jurassic and Triassic strata;diagenetically-modified connate marine water from the Cambrian and Ordovician strata; subaerially-evaporated water from the Cenozoic and Cretaceous strata; and mixed meteoric-evaporated or/and diagenetically modified connate water from the Carboniferous strata and reservoirs adjacent to the J/C and T/C unconformities. Those waters with very negativeδD values from -51. 30‰. to - 53. 80‰ (SMOW) and positive δ18 O values from 2. 99‰ to 4. 99‰(SMOW) in the continuous burial of the Cambrian-Ordovician system are explained to have resulted from hydrocarbon-water and water-rock interactions. 展开更多
关键词 水岩反应 油田 水文地球化学 氧同位素 氢同位素 塔里木盆地
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Hydrogeochemical Simulation of Water-Rock Interaction Under Water Flood Recovery in Renqiu Oilfield, Hebei Province, China 被引量:1
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作者 冯启言 韩宝平 《Chinese Journal Of Geochemistry》 EI CAS 2002年第2期156-162,共7页
Hydrogeochemical simulation is an effective method to study water-rock interaction. In this paper, PHREEQM was used for the simulation of water-rock interaction under water flooding in the Renqiu Oilfield. Calculated ... Hydrogeochemical simulation is an effective method to study water-rock interaction. In this paper, PHREEQM was used for the simulation of water-rock interaction under water flooding in the Renqiu Oilfield. Calculated results revealed that when fresh water was injected into the reservoir, Cl\+- and Na\++ would decrease without involvement in water-rock interaction. Erosion to dolomite will lead to an increase in Ca\+\{2+\}, Mg\+\{2+\} and CaHCO\++\-3. Saturation index of calcite and aragonite decreased first and then increased. With fresh water accounting for up to 70%, mixed water has the strongest erosion ability. Deoiled water has erosion ability under high temperature and high partial pressure of CO\-2. Pyrite and gypsum were sensitive to deoiled water, which can cause the dissolution of pyrite and the precipitation of gypsum. Micrographs revealed a great deal of information about water-rock interaction. 展开更多
关键词 水岩反应 河北 热化学模拟 油田
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Test of subcritical crack growth and fracture toughness under water-rock interaction in three types of rocks 被引量:6
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作者 郝瑞卿 李江腾 +2 位作者 曹平 刘博 廖峻 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第2期662-668,共7页
The subcritical crack growth and fracture toughness in peridotite, lherzolite and amphibolite were investigated with double torsion test. The results show that water-rock interaction has a significant influence on sub... The subcritical crack growth and fracture toughness in peridotite, lherzolite and amphibolite were investigated with double torsion test. The results show that water-rock interaction has a significant influence on subcritical crack growth. With water-rock interaction, the crack velocity increases, while the stress intensity factor declines, which illustrates that water-rock interaction can decrease the strength of rocks and accelerate the subcritical crack growth. Based on Charlse theory and Hilling & Charlse theory, the test data were analyzed by regression and the correlation coefficients were all higher than 0.7, which shows the correlation is significant. This illustrates that both theories can explain the results of tests very well. Therefore, it is believed that the subcritical crack growth attributes to the breaking of chemical bond, which is caused by the combined effect of the tensile stress and the chemical reaction between the material at crack tip and the corrosive agent. Meanwhile, water-rock interaction has a vital effect on fracture toughness. The fracture toughness of samples under atmospheric environment is higher than that of samples immersed in water. And water-rock interaction has larger influence on fracture toughness in amphibolite than that in peridotite and lherzolite. 展开更多
关键词 亚临界裂纹扩展 断裂韧性 相互作用 测试数据 明水 岩石 二辉橄榄岩 应力强度因子
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Strontium isotope composition of the Arno River Valley waters (Tuscany, Italy) as a natural tracer of water-rock interaction and mixing processes 被引量:2
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作者 Barbara Nisi Orlando Vaselli +4 位作者 Antonella Buccianti Giulia Perini Angelo Minissale Giordano Montegrossi Franco Tassi 《Chinese Journal Of Geochemistry》 EI CAS 2006年第B08期273-273,共1页
关键词 意大利 河流 同位素 水文化学
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Biological Interaction and Imaging of Ultrasmall Gold Nanoparticles
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作者 Dongmiao Sang Xiaoxi Luo Jinbin Liu 《Nano-Micro Letters》 SCIE EI CSCD 2024年第3期69-98,共30页
Ultrasmall gold nanoparticles(AuNPs)typically includes atomically precise gold nanoclusters(AuNCs)and AuNPs with a core size below 3 nm.Serving as a bridge between small molecules and traditional inorganic nanoparticl... Ultrasmall gold nanoparticles(AuNPs)typically includes atomically precise gold nanoclusters(AuNCs)and AuNPs with a core size below 3 nm.Serving as a bridge between small molecules and traditional inorganic nanoparticles,the ultrasmall AuNPs show the unique advantages of both small molecules(e.g.,rapid distribution,renal clearance,low non-specific organ accumulation)and nanoparticles(e.g.,long blood circulation and enhanced permeability and retention effect).The emergence of ultrasmall AuNPs creates significant opportunities to address many challenges in the health field including disease diagnosis,monitoring and treatment.Since the nano–bio interaction dictates the overall biological applications of the ultrasmall AuNPs,this review elucidates the recent advances in the biological interactions and imaging of ultrasmall AuNPs.We begin with the introduction of the factors that influence the cellular interactions of ultrasmall AuNPs.We then discuss the organ interactions,especially focus on the interactions of the liver and kidneys.We further present the recent advances in the tumor interactions of ultrasmall AuNPs.In addition,the imaging performance of the ultrasmall AuNPs is summarized and discussed.Finally,we summarize this review and provide some perspective on the future research direction of the ultrasmall AuNPs,aiming to accelerate their clinical translation. 展开更多
关键词 Ultrasmall gold nanoparticle Cellular interaction Organ interaction Tumor interaction BIOIMAGING
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Ecological network analysis reveals complex responses of tree species life stage interactions to stand variables
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作者 Hengchao Zou Huayong Zhang Tousheng Huang 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第1期29-43,共15页
Tree interactions are essential for the structure,dynamics,and function of forest ecosystems,but variations in the architecture of life-stage interaction networks(LSINs)across forests is unclear.Here,we constructed 16... Tree interactions are essential for the structure,dynamics,and function of forest ecosystems,but variations in the architecture of life-stage interaction networks(LSINs)across forests is unclear.Here,we constructed 16 LSINs in the mountainous forests of northwest Hebei,China based on crown overlap from four mixed forests with two dominant tree species.Our results show that LSINs decrease the complexity of stand densities and basal areas due to the interaction cluster differentiation.In addition,we found that mature trees and saplings play different roles,the first acting as“hub”life stages with high connectivity and the second,as“bridges”controlling information flow with high centrality.Across the forests,life stages with higher importance showed better parameter stability within LSINs.These results reveal that the structure of tree interactions among life stages is highly related to stand variables.Our efforts contribute to the understanding of LSIN complexity and provide a basis for further research on tree interactions in complex forest communities. 展开更多
关键词 Tree interactions Life stages interaction networks Ecological complexity
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Study of the Relationship Between New Ionic Interaction Parameters and Salt Solubility in Electrolyte Solutions Based on Molecular Dynamics Simulation
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作者 SUN Wenting HU Yangdong +5 位作者 ZHENG Jiahuan SUN Qichao Chen Xia DING Jiakun ZHANG Weitao WU Lianying 《Journal of Ocean University of China》 CAS CSCD 2024年第2期467-476,共10页
Studying the relationship between ionic interactions and salt solubility in seawater has implications for seawater desalination and mineral extraction.In this paper,a new method of expressing ion-to-ion interaction is... Studying the relationship between ionic interactions and salt solubility in seawater has implications for seawater desalination and mineral extraction.In this paper,a new method of expressing ion-to-ion interaction is proposed by using molecular dynamics simulation,and the relationship between ion-to-ion interaction and salt solubility in a simulated seawater water-salt system is investigated.By analyzing the variation of distance and contact time between ions in an electrolyte solution,from both spatial and temporal perspectives,new parameters were proposed to describe the interaction between ions:interaction distance(ID),and interaction time ratio(ITR).The best correlation between characteristic time ratio and solubility was found for a molar ratio of salt-to-water of 10:100 with a correlation coefficient of 0.96.For the same salt,a positive correlation was found between CTR and the molar ratio of salt and water.For type 1-1,type 2-1,type 1-2,and type 2-2 salts,the correlation coefficients between CTR and solubility were 0.93,0.96,0.92,and 0.98 for a salt-to-water molar ratio of 10:100,respectively.The solubility of multiple salts was predicted by simulations and compared with experimental values,yielding an average relative deviation of 12.4%.The new ion-interaction parameters offer significant advantages in describing strongly correlated and strongly hydrated electrolyte solutions. 展开更多
关键词 molecular dynamics simulation interaction distance interaction time rate electrolyte aqueous solutions SOLUBILITY
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Interatomic Interaction Models for Magnetic Materials:Recent Advances
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作者 Tatiana S.Kostiuchenko Alexander V.Shapeev Ivan S.Novikov 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第6期54-66,共13页
Atomistic modeling is a widely employed theoretical method of computational materials science.It has found particular utility in the study of magnetic materials.Initially,magnetic empirical interatomic potentials or s... Atomistic modeling is a widely employed theoretical method of computational materials science.It has found particular utility in the study of magnetic materials.Initially,magnetic empirical interatomic potentials or spinpolarized density functional theory(DFT)served as the primary models for describing interatomic interactions in atomistic simulations of magnetic systems.Furthermore,in recent years,a new class of interatomic potentials known as magnetic machine-learning interatomic potentials(magnetic MLIPs)has emerged.These MLIPs combine the computational efficiency,in terms of CPU time,of empirical potentials with the accuracy of DFT calculations.In this review,our focus lies on providing a comprehensive summary of the interatomic interaction models developed specifically for investigating magnetic materials.We also delve into the various problem classes to which these models can be applied.Finally,we offer insights into the future prospects of interatomic interaction model development for the exploration of magnetic materials. 展开更多
关键词 MATERIALS interaction empirical
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Resistive field generation in intense proton beam interaction with solid targets
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作者 W.Q.Wang J.J.Honrubia +2 位作者 Y.Yin X.H.Yang F.Q.Shao 《Matter and Radiation at Extremes》 SCIE EI CSCD 2024年第1期35-43,共9页
The Brown-Preston-Singleton(BPS)stopping power model is added to our previously developed hybrid code to model ion beam-plasma interaction.Hybrid simulations show that both resistive field and ion scattering effects a... The Brown-Preston-Singleton(BPS)stopping power model is added to our previously developed hybrid code to model ion beam-plasma interaction.Hybrid simulations show that both resistive field and ion scattering effects are important for proton beam transport in a solid target,in which they compete with each other.When the target is not completely ionized,the self-generated resistive field effect dominates over the ion scattering effect.However,when the target is completely ionized,this situation is reversed.Moreover,it is found that Ohmic heating is important for higher current densities and materials with high resistivity.The energy fraction deposited as Ohmic heating can be as high as 20%-30%.Typical ion divergences with half-angles of about 5°-10°will modify the proton energy deposition substantially and should be taken into account. 展开更多
关键词 interaction BEAM INTENSE
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Dynamical nonlinear excitations induced by interaction quench in a two-dimensional box-trapped Bose-Einstein condensate
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作者 牛真霞 高超 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期209-215,共7页
Manipulating nonlinear excitations,including solitons and vortices,is an essential topic in quantum many-body physics.A new progress in this direction is a protocol proposed in[Phys.Rev.Res.2043256(2020)]to produce da... Manipulating nonlinear excitations,including solitons and vortices,is an essential topic in quantum many-body physics.A new progress in this direction is a protocol proposed in[Phys.Rev.Res.2043256(2020)]to produce dark solitons in a one-dimensional atomic Bose–Einstein condensate(BEC)by quenching inter-atomic interaction.Motivated by this work,we generalize the protocol to a two-dimensional BEC and investigate the generic scenario of its post-quench dynamics.For an isotropic disk trap with a hard-wall boundary,we find that successive inward-moving ring dark solitons(RDSs)can be induced from the edge,and the number of RDSs can be controlled by tuning the ratio of the after-and before-quench interaction strength across different critical values.The role of the quench played on the profiles of the density,phase,and sound velocity is also investigated.Due to the snake instability,the RDSs then become vortex–antivortex pairs with peculiar dynamics managed by the initial density and the after-quench interaction.By tuning the geometry of the box traps,demonstrated as polygonal ones,more subtle dynamics of solitons and vortices are enabled.Our proposed protocol and the discovered rich dynamical effects on nonlinear excitations can be realized in near future cold-atom experiments. 展开更多
关键词 Bose-Einstein condensate quench interaction SOLITON vortex
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Effect of electron-electron interaction on polarization process of exciton and biexciton in conjugated polymer
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作者 李晓雪 彭华 +1 位作者 王栋 侯栋 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期556-566,共11页
By using one-dimensional tight-binding model modified to include electron-electric field interaction and electron-electron interaction,we theoretically explore the polarization process of exciton and biexciton in cis-... By using one-dimensional tight-binding model modified to include electron-electric field interaction and electron-electron interaction,we theoretically explore the polarization process of exciton and biexciton in cis-polyacetylene.The dynamical simulation is performed by adopting the non-adiabatic evolution approach.The results show that under the effect of moderate electric field,when the strength of electron-electron interaction is weak,the singlet exciton is stable but its polarization presents obvious oscillation.With the enhancement of interaction,it is dissociated into polaron pairs,the spin-flip of which can be observed through modulating the interaction strength.For the triplet exciton,the strong electron-electron interaction restrains its normal polarization,but it is still stable.In the case of biexciton,the strong electron-electron interaction not only dissociate it,but also flip its charge distribution.The yield of the possible states formed after the dissociation of exciton and biexciton is also calculated. 展开更多
关键词 conjugated polymer EXCITON electron-electron interaction reverse polarization
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Silica-modified Pt/TiO_(2) catalysts with tunable suppression of strong metal-support interaction for cinnamaldehyde hydrogenation
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作者 Zhengjian Hou Yuanyuan Zhu +6 位作者 Hua Chi Li Zhao Huijie Wei Yanyan Xi Lishuang Ma Xiang Feng Xufeng Lin 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第6期189-198,共10页
Tuning Strong Metal-support Interactions(SMSI)is a key strategy to obtain highly active catalysts,but conventional methods usually enable TiO encapsulation of noble metal components to minimize the exposure of noble m... Tuning Strong Metal-support Interactions(SMSI)is a key strategy to obtain highly active catalysts,but conventional methods usually enable TiO encapsulation of noble metal components to minimize the exposure of noble metals.This study demonstrates a catalyst preparation method to modulate a weak encapsulation of Pt metal nanoparticles(NPs)with the supported TiO_(2),achieving the moderate suppression of SMSI effects.The introduction of silica inhibits this encapsulation,as reflected in the characterization results such as XPS and HRTEM,while the Ti4+to Ti3+conversion due to SMSI can still be found on the support surface.Furthermore,the hydrogenation of cinnamaldehyde(CAL)as a probe reaction revealed that once this encapsulation behavior was suppressed,the adsorption capacity of the catalyst for small molecules like H_(2) and CO was enhanced,which thereby improved the catalytic activity and facilitated the hydrogenation of CAL.Meanwhile,the introduction of SiO_(2) also changed the surface structure of the catalyst,which inhibited the occurrence of the acetal reaction and improved the conversion efficiency of C=O and C=C hydrogenation.Systematic manipulation of SMSI formation and its consequence on the performance in catalytic hydrogenation reactions are discussed. 展开更多
关键词 Pt catalyst SILICA modification HYDROGENATION CINNAMALDEHYDE STRONG metal-support interaction
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Dynamics of Non-Markovianity, Quantum Correlations and Information Scrambling of Three Qubits Systems Interacting via Rashba Interaction
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作者 Nasser Metwally Fawzeya Ebrahim 《Journal of Quantum Information Science》 CAS 2024年第2期52-67,共16页
The behavior of the quantum correlations, information scrambling and the non-Markovianity of three entangling qubits systems via Rashba is discussed. The results showed that, the three physical quantities oscillate be... The behavior of the quantum correlations, information scrambling and the non-Markovianity of three entangling qubits systems via Rashba is discussed. The results showed that, the three physical quantities oscillate between their upper and lower bounds, where the number of oscillations increases as the Rashba interaction strength increases. The exchanging rate of these three quantities depends on the Rashba strength, and whether the entangled state is generated via direct/indirect interaction. Moreover, the coherence parameter can be used as a control parameter to maximize or minimize the three physical quantities. 展开更多
关键词 Markovianity Correlations Rashba interaction Scrambling Information
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Interaction between adolescent sleep rhythms and gender in an obese population
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作者 Nan-Nan Wu Guo-Li Yan +3 位作者 Hong-Yu Zhang Ling Sun Min Hou Guang-Ming Xu 《World Journal of Clinical Cases》 SCIE 2024年第1期86-94,共9页
BACKGROUND The obesity rate of adolescents is gradually increasing,which seriously affects their mental health,and sleep plays an important role in adolescent obesity.AIM To investigate the relationship between sleep ... BACKGROUND The obesity rate of adolescents is gradually increasing,which seriously affects their mental health,and sleep plays an important role in adolescent obesity.AIM To investigate the relationship between sleep rhythm and obesity among adolescents and further explores the interactive effect of sleep rhythm and gender on adolescent obesity,providing a theoretical basis for developing interventions for adolescent obesity.METHODS Research data source Tianjin Mental Health Promotion Program for Students.From April to June 2022,this study selected 14201 students from 13 middle schools in a certain district of Tianjin as the research subject using the convenient cluster sampling method.Among these students,13374 accepted and completed the survey,with an effective rate of 94.2%.The demographic data and basic information of adolescents,such as height and weight,were collected through a general situation questionnaire.The sleep rhythm of adolescents was evaluated using the reduced version of the morningness-eveningness questionnaire.RESULTS A total of 13374 participants(6629 females,accounting for 49.56%;the average age is 15.21±1.433 years)were analyzed.Among them,the survey showed that 2942 adolescent were obesity,accounting for 22%and 2104 adolescent were overweight,accounting for 15.7%.Among them,1692 male adolescents are obese,with an obesity rate of 25.1%,higher than 18.9%of female adolescents.There is a statistically significant difference between the three groups(χ2=231.522,P<0.000).The obesity group has the smallest age(14.94±1.442 years),and there is a statistical difference in age among the three groups(F=69.996,P<0.000).Obesity rates are higher among individuals who are not-only-child,have residential experience within six months,have family economic poverty,and have evening-type sleep(P<0.05).Logistic regression analysis shows a correlation between sleep rhythm and adolescent obesity.Evening-type sleep rhythm can increase the risk of obesity in male adolescents[1.250(1.067-1.468)],but the effect on female obesity is not remarkable.Further logistic regression analysis in the overall population demonstrates that the interaction between evening-type sleep rhythm and the male gender poses a risk of adolescent obesity[1.122(1.043-1.208)].CONCLUSION Among adolescents,the incidence of obesity in males is higher than in females.Evening-type sleep rhythm plays an important role in male obesity but has no significant effect on female obesity.Progressive analysis suggests an interactive effect of sleep rhythm and gender on adolescent obesity,and the combination of evening-type sleep and the male gender promotes the development of adolescent obesity.In formulating precautions against adolescent obesity,obesity in male adolescents with evening-type sleep should be a critical concern. 展开更多
关键词 ADOLESCENT OBESITY Sleep rhythm GENDER interaction
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Actively tuning anisotropic light-matter interaction in biaxial hyperbolic materialα-MoO_(3) using phase change material VO_(2) and graphene
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作者 周昆 胡杨 +2 位作者 吴必园 仲晓星 吴小虎 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期631-638,共8页
Anisotropic hyperbolic phonon polaritons(PhPs)in natural biaxial hyperbolic materialα-MoO_(3) has opened up new avenues for mid-infrared nanophotonics,while active tunability ofα-MoO_(3) PhPs is still an urgent prob... Anisotropic hyperbolic phonon polaritons(PhPs)in natural biaxial hyperbolic materialα-MoO_(3) has opened up new avenues for mid-infrared nanophotonics,while active tunability ofα-MoO_(3) PhPs is still an urgent problem necessarily to be solved.In this study,we present a theoretical demonstration of actively tuningα-MoO_(3) PhPs using phase change material VO_(2) and graphene.It is observed thatα-MoO_(3) PhPs are greatly dependent on the propagation plane angle of PhPs.The insulator-to-metal phase transition of VO_(2) has a significant effect on the hybridization PhPs of theα-MoO_(3)/VO_(2) structure and allows to obtain actively tunableα-MoO_(3) PhPs,which is especially obvious when the propagation plane angle of PhPs is 900.Moreover,when graphene surface plasmon sources are placed at the top or bottom ofα-MoO_(3) inα-MoO_(3)/VO_(2)structure,tunable coupled hyperbolic plasmon-phonon polaritons inside its Reststrahlen bands(RB s)and surface plasmonphonon polaritons outside its RBs can be achieved.In addition,the above-mentionedα-MoO_(3)-based structures also lead to actively tunable anisotropic spontaneous emission(SE)enhancement.This study may be beneficial for realization of active tunability of both PhPs and SE ofα-MoO_(3),and facilitate a deeper understanding of the mechanisms of anisotropic light-matter interaction inα-MoO_(3) using functional materials. 展开更多
关键词 light-matter interaction hyperbolic material phase change material GRAPHENE
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