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In situ Raman spectroscopic investigation of copper speciation in hydrothermal fluids at temperatures up to 300℃
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作者 Zhenglong Wang Linbo Shang +6 位作者 I-Ming Chou Chen Chen Yunhe Zhou Jianguo Li Ziqi Jiang Xinwei Gao Ye Wan 《Acta Geochimica》 2026年第1期142-154,共13页
The formation of copper deposits is closely related to hydrothermal processes.Understanding the migration of copper in hydrothermal fluids aids in reconstructing mineralization processes and deciphering deposit genesi... The formation of copper deposits is closely related to hydrothermal processes.Understanding the migration of copper in hydrothermal fluids aids in reconstructing mineralization processes and deciphering deposit genesis.Copper primarily exists as Cu^(+)and Cu^(2+)in hydrothermal solutions,with redox conditions governing their interconversion.In chloride-rich geological fluids,Cu-Cl complexes are considered critical for copper transport.However,the specific types and valence transitions of Cu-Cl complexes under varying hydrothermal conditions remain poorly understood.This study employed in situ Raman spectroscopy to systematically analyze Cu+HCl and CuCl_(2)+K_(2)S_(2)O_(3)/H_(2) systems under saturated vapor pressure at 25-300℃,elucidating the effects of temperature,Cl^(-)concentration,and redox conditions on copper speciation.In the Cu^(+)HCl system,copper dissolved as monovalent Cu-Cl complexes.At high temperatures(>200℃),[CuCl_(2)]^(-)is the dominated species,whereas[CuCl_(3)]^(2-)becomes prevalent at lower temperatures and higher HCl concentrations.For the Cu^(2+)-Cl system,the dominant species transitioned from[Cu(H_(2)O)n]^(2+)(<50℃)to[CuCl_(4)]^(2-)(100℃)and further to[CuCl]^(+)and[CuCl_(2)]^(0) at 300℃.The introduction of reducing agents(K_(2)S_(2)O_(3)/H_(2))facilitated Cu^(2+)→Cu^(+)reduction,thereby stabilizing Cu^(+)-Cl complexes and inducing partial copper precipitation.The behavior of copper in chloriderich hydrothermal fluids observed in this study indicates that high-temperature oxidizing fluids facilitate Cu mobilization,while cooling and redox changes promote deposition and ore minerals formation. 展开更多
关键词 Raman spectroscopy In situ analysis Hydrothermal fluids COPPER Transport mechanism
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Subretinal fluid in rhegmatogenous retinal detachment:potential biomarkers and therapeutic targets for proliferative vitreoretinopathy
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作者 Yi-Shuang Mao Wei-Hong Yu 《International Journal of Ophthalmology(English edition)》 2026年第1期175-180,共6页
Rhegmatogenous retinal detachment(RRD)is a serious ocular condition marked by the separation of the neuroretina from the retinal pigment epithelium(RPE).The pathogenesis of RRD involves intricate molecular and cellula... Rhegmatogenous retinal detachment(RRD)is a serious ocular condition marked by the separation of the neuroretina from the retinal pigment epithelium(RPE).The pathogenesis of RRD involves intricate molecular and cellular mechanisms,including inflammation,cell migration,and the activation of proliferative signaling pathways.One of the most challenging complications of RRD is proliferative vitreoretinopathy(PVR),which refers to the proliferation and contraction of fibrocellular membranes on the retinal surface and in the vitreous cavity.PVR is a major cause of surgical failure in RRD,as it can lead to recurrent retinal detachment and severe vision loss.However,the pathogenesis of PVR is not yet fully understood,and the treatment options are quite limited.Recent advances in analytical techniques have offered valuable insights into the molecular alterations present in the subretinal fluid(SRF)of patients with RRD.This review seeks to consolidate the current knowledge regarding the SRF profile in RRD and PVR,emphasizing potential biomarkers and therapeutic targets. 展开更多
关键词 proliferative vitreoretinopathy rhegmatogenous retinal detachment subretinal fluid
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A comparison of porous sandstone fracturing induced by increasing fluid pressure or decreasing confining pressure:Stress-path and rate-dependence effects
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作者 Xu Han Lei Wang +2 位作者 Erik Rybacki Marco Bohnhoff Georg Dresen 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第1期151-165,共15页
When a porous rock is subjected to overall compressive loading,either increasing pore pressure or decreasing confining pressure could result in rock failure.The stress path and the applied pressure change rate may aff... When a porous rock is subjected to overall compressive loading,either increasing pore pressure or decreasing confining pressure could result in rock failure.The stress path and the applied pressure change rate may affect the initiation and propagation of fractures within brittle materials.Understanding the physical mechanisms leading to failure is crucial for underground engineering applications and geo-energy exploration and storage.We conducted triaxial compression experiments on porous Bentheim sandstone samples at different stress paths and pressure change rates.First,at a constant confining pressure of 35 MPa and pore pressure of 5 MPa,intact cylindrical samples were axially loaded up to about 85%of the peak strength.Subsequently,the axial piston position was fixed,and then either the pore pressure was increased or the confining pressure was decreased at two different rates(0.5 MPa/min or 2 MPa/min),leading to final catastrophic failure.The mechanical results revealed that samples subjected to higher rates of decreasing effective confining pressure exhibited larger stress drop rates,higher slip rates,higher total breakdown work,higher rates of acoustic emissions(AEs)before failure,and higher post-failure AE decay rates.In contrast,the applied stress path did not significantly affect rock failure characteristics.Comparison of located AE events with post-mortem microstructures of deformed samples shows a good agreement.The AE source type determined from the P-wave first-motion polarity shows that shear failure dominated the fracture process when approaching failure.Gutenberg-Richter b-values revealed a significant decrease before failure in all tests.Our results indicate that,in contrast to the stress path,the rate of effective stress change strongly affects fracturing behavior and AE rate changes. 展开更多
关键词 Porous sandstone fluid injection Effective confining pressure changing rate Stress path
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Fluid migration in calcite nanopores under salinity gradients:Insights from molecular dynamics
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作者 Yi Chen Yan Zhang +1 位作者 Run-Sheng Han Lei Wang 《Acta Geochimica》 2026年第1期185-203,共19页
The migration mechanisms of ore-forming fluids have long been a focus in the field of ore deposit studies.Calcite is ubiquitously present in various types of rocks in the lithosphere,and the underlying mechanisms of i... The migration mechanisms of ore-forming fluids have long been a focus in the field of ore deposit studies.Calcite is ubiquitously present in various types of rocks in the lithosphere,and the underlying mechanisms of its influence on fluid migration are of crucial importance.While previous studies have revealed that salinity changes can modulate fluid migration,the underlying mechanisms remain poorly understood.We employ molecular dynamics simulations to elucidate how salinity variations in ore-forming fluids modulate the adsorption onto calcite nanopore walls,thereby revealing the microscopic mechanisms governing ore fluid transport through calcite nano-fractures.The results show that the adsorption energy Eint of the solution on the calcite surface increased from -14,948.84±182.48 kcal/mol to -12,144.08±118.2 kcal/mol as salinity increased,which is conducive to the long-range transport of the fluid in the calcite nanopore. 展开更多
关键词 fluid transport dynamics Salinity gradient regulation Calcite nanopores Molecular dynamics simulation
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Optical lateral flow immune assay technology for body fluid sensing
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作者 Chen Liu Tianqi Zhao +5 位作者 Jialing Zhou Xiaoyun Hu Dinghao Pan Jinlong Li Wei Li Zhihui Dai 《Chinese Chemical Letters》 2026年第1期106-115,共10页
Detecting biomarkers in body fluids by optical lateral flow immune assay(LFIA) technology provides rapid access to disease information for early diagnosis.LFIA is based on an antigen-antibody reaction and is rapidly b... Detecting biomarkers in body fluids by optical lateral flow immune assay(LFIA) technology provides rapid access to disease information for early diagnosis.LFIA is based on an antigen-antibody reaction and is rapidly becoming the preferred choice of physicians and patients for point-of-care testing due to its simplicity,cost-effectiveness,and rapid detection.Observing the optical signal change from the colloidal gold of the traditional LFIA strip has been widely applied for various biomarkers detection in body fluids.Despite the significant progress,rapid real-time detection of color changes in the colloidal gold by the naked eye still faces many limitations,such as large errors and the inability to quantify and accurately detect.New optical LFIA strip technology has emerged in recent years to extend its application scenarios for achieving quantitative detection such as fluorescence,afterglow,and chemiluminescence.Herein,we summarized the development of optical LFIA technology from single to hyphenated optical signals for biomarkers detection in body fluids from invasive and non-invasive sources.Moreover,the challenge and outlook of optical LFIA strip technology are highlighted to inspire the designing of next-generation diagnostic platforms. 展开更多
关键词 Optical signal Lateral flow immune assay Hyphenated optical technology Body fluid sensing Point-of-care testing
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Reactivation of rate-and-state faults induced by CO_(2)injection:Effects of pore pressure diffusion and fluid pressurization
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作者 Yao Zhang Qi Li +2 位作者 Xiaying Li Yongsheng Tan Meng Jing 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第2期954-970,共17页
While injection-induced seismicity has been widely studied,its implications for CO_(2)geological storage require reevaluation due to distinct fluid-rock interactions.This study develops a coupled hydromechanical model... While injection-induced seismicity has been widely studied,its implications for CO_(2)geological storage require reevaluation due to distinct fluid-rock interactions.This study develops a coupled hydromechanical model incorporating rate-and-state friction laws to investigate fault reactivation mechanisms during early-stage CO_(2)injection.The competing effects of pore pressure diffusion and fluid pressurization are systematically investigated,considering three key factors:permeability variations within fault damage zones,normal stress variation coefficients,and injection parameters.Numerical simulations reveal that slower CO_(2)migration causes limited pressure perturbation(<0.3 MPa over 15 d)compared to single-phase fluid injection.Fluid pressurization enhances fault strength and delays reactivation,though this stabilizing effect diminishes in low-permeability damage zones.Highly permeable damage zones promote larger rupture areas despite strengthening from pressurization,as reduced effective stress accelerates failure.Paradoxically,while fluid pressurization increases fault strength,it simultaneously elevates seismic risk through amplified stress drops during slip events.Temporal analysis shows that fluid pressurization dominates initial fault response,while sustained pore pressure diffusion ultimately drives reactivation.Increased normal stress variation coefficients and injection rates accelerate localized rupture initiation but restrict propagation due to non-critically stressed states.This discrepancy demonstrates that regions with positive Coulomb failure stress changes do not correlate well with actual slip zones.These findings highlight the critical interplay between transient pressurization effects and progressive pressure diffusion during early CO_(2)injection phases,providing crucial insights for seismic risk management in CO_(2)storage projects. 展开更多
关键词 CO_(2)geological storage Induced seismicity Fault reactivation fluid pressurization
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Fluid mechanics approach to assess airflow dynamics during the respiratory cycle in a child nasal airway with adenoid hypertrophy
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作者 Zahid Ullah Khan Xizhuo Jiang +1 位作者 Jingliang Dong Xiaodong Wang 《Acta Mechanica Sinica》 2026年第1期162-177,共16页
The airflow mechanics in adult nasal airways,whether healthy or abnormal,are extensively studied and investigated,but the flow mechanics in child nasal airways remain underexplored.This study investigates the airflow ... The airflow mechanics in adult nasal airways,whether healthy or abnormal,are extensively studied and investigated,but the flow mechanics in child nasal airways remain underexplored.This study investigates the airflow mechanics in the child’s nasal upper airway with adenoid hypertrophy,with an adenoid nasopharyngeal ratio(AN of 0.9),under cyclic inhalation and exhalation.An inlet respiratory cycle with three different flow rates(3.2 L/min calm breathing,8.6 L/min normal breathing,and 19.3 L/min intensive breathing)was simulated by using the computational fluid dynamics approach.To better capture the interaction between airflow and the flexible airway tissue,fluid-structure interaction analysis was performed at the normal breathing rate.Comparing the airflow dynamics during inhalation and exhalation,the pressure drops,nasal resistance,and wall shear stress show significant differences in the nasopharyngeal region for all different flow rates.This observation suggests that the inertial effect associated with the transient flow is important during exhalation and inhalation.Furthermore,the considerable temporal variation in flow rate distribution across a specific cross-section of the nasal airway highlights the critical role of transient data in virtual surgery planning and data for clinical decisions. 展开更多
关键词 Computational fluid dynamics Child nasal airway Nasal breathing cycle Flow mechanics Nasal resistance Pressure drop Wall shear stress
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Pressure dependence of the structures and transport properties of supercritical NaAlSi_(3)O_(8)-H_(2)O fluids
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作者 Ziteng Long Yicheng Sun 《Acta Geochimica》 2026年第1期155-167,共13页
Supercritical fluids play a crucial role in material transport within Earth's deep interior.Investigating the pressure-dependent atomic structures and transport properties of such fluids is essential for understan... Supercritical fluids play a crucial role in material transport within Earth's deep interior.Investigating the pressure-dependent atomic structures and transport properties of such fluids is essential for understanding their petrological,chemical,and geophysical behaviors.In this study,we employed first-principles molecular dynamics simulations to explore the structures,self-diffusion coefficients(D),and viscosities(η)of supercritical NaAlSi_(3)O_(8)-H_(2)O fluids under conditions of 2000 K and 3-10 GPa,with water contents of 30 wt% and 50 wt%.Our calculations indicate that at a water content of 30 wt%,Q^(2) and Q^(3) exhibit a certain degree of positive and negative pressure dependence,respectively,while other Q^(n) species(n represents the number of bridging oxygens connected to Si/Al)show minimal changes.At a water content of 50 wt%,Q^(2) and Q^(0) exhibit a certain degree of positive and negative pressure dependence,respectively,while other Q^(n) species show minimal changes.At both water contents,Si-O-H and molecular water in the system exhibit negative pressure dependence,suggesting that the migration of supercritical fluids from deep to shallow regions is accompanied by the release of water.The self-diffusion coefficients in the supercritical NaAlSi_(3)O_(8)-H_(2)O fluid follow the order D_(Na)≈D_(H)>D_(O)>D_(Al)≈D_(Si),with an overall weak negative pressure dependence.By comparing the viscosities of anhydrous and hydrous silicate melts from previous studies,we found that the addition of water caused a transition from negative to positive pressure dependence of viscosity,corresponding to a structural change from polymerization to depolymerization.Additionally,we calculated the fluid mobility Δp/η of supercritical NaAlSi_(3)O_(8)-H_(2)O fluids and found that their mobility is several orders of magnitude higher than that of basalt melt and is also significantly greater than that of carbonate melt.As supercritical fluids ascend from deeper to shallower regions,their mobility is further enhanced,significantly contributing to the transport of elements from subducting slabs to the overlying mantle wedge. 展开更多
关键词 Supercritical fluids NaAlSi_(3)O_(8)-H_(2)O Firstprinciples SPECIATION Transport properties
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Reservoir fluid type identification method based on deep learning:A case study of the Chang 1 Formation in the Jiyuan oilfield of the Ordos basin,China
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作者 Wen-bo Li Xiao-ye Wang +4 位作者 Lei He Zhen-kai Zhang Zeng-lin Hong Ling-yi Liu Dong-tao Li 《China Geology》 2026年第1期60-74,共15页
With the efficient and intelligent development of computer-based big data processing,applying machine learning methods to the processing and interpretation of logging data in the field of geophysical well logging has ... With the efficient and intelligent development of computer-based big data processing,applying machine learning methods to the processing and interpretation of logging data in the field of geophysical well logging has broad potential for improving production efficiency.Currently,the Jiyuan Oilfield in the Ordos Basin relies mainly on manual reprocessing and interpretation of old well logging data to identify different fluid types in low-contrast reservoirs,guiding subsequent production work.This study uses well logging data from the Chang 1 reservoir,partitioning the dataset based on individual wells for model training and testing.A deep learning model for intelligent reservoir fluid identification was constructed by incorporating the focal loss function.Comparative validations with five other models,including logistic regression(LR),naive Bayes(NB),gradient boosting decision trees(GBDT),random forest(RF),and support vector machine(SVM),show that this model demonstrates superior identification performance and significantly improves the accuracy of identifying oil-bearing fluids.Mutual information analysis reveals the model's differential dependency on various logging parameters for reservoir fluid identification.This model provides important references and a basis for conducting regional studies and revisiting old wells,demonstrating practical value that can be widely applied. 展开更多
关键词 Low-contrast reservoirs fluid types Pore structure Clay content LR+NB+GBDT+RF+SVM model Machine learning Neural networks Loss functions Geophysical well logging Oil and gas reservoir prediction
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Neonatal bone marrow interstitial fluid supports expansion and osteogenic ability of human bone marrow mesenchymal stromal cells
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作者 Junfeng Zhang Tengjiao Ma +5 位作者 Lan Ke Huan Zhang Jiaxin Hu Shunping Li Hailong Wang Anming Meng 《Bone Research》 2025年第6期1599-1612,共14页
The bone marrow microenvironment is critical for the maintenance and functionality of stem/progenitor cells,which are essential for bone development and regeneration.However,the composition and potential use of bone m... The bone marrow microenvironment is critical for the maintenance and functionality of stem/progenitor cells,which are essential for bone development and regeneration.However,the composition and potential use of bone marrow interstitial fluid have not been well explored.In this study,we report the role of neonatal bovine bone marrow interstitial fluid(NBIF)in enhancing the bone regeneration capacity of human bone marrow mesenchymal stem cells(hBMSCs).Unlike adult bovine bone marrow interstitial fluid(ABIF),NBIF-fed hBMSCs exhibit enhanced self-renewal and osteogenic potential and bone marrow homing ability,along with transcriptome changes as compared to hBMSCs cultured in standard fetal bovine serum(FBS)supplemented medium.Mass spectrometry analysis reveals that multiple secreted factors associated with tissue repair and bone development are enriched in NBIF compared to FBS and ABIF.The combined use of NBIF-enriched Nerve Growth Factor(NGF),Lactoferrin(LTF),and High Mobility Group Protein B1(HMGB1),together with Insulin-Like Growth Factor 1(IGF1)for culturing hBMSCs in the presence of FBS can enhance osteogenic potential and bone marrow homing ability,mimicking NBIF's effects.These findings highlight the role of interstitial fluid in the bone marrow microenvironment and its potential to optimize stem cell-based therapies. 展开更多
关键词 human bone marrow mesenchymal stem cells bone marrow interstitial fluid enhancing bone regeneration capacity bone marrow interstitial fluid nbif neonatal bovine bone marrow interstitial fluid osteogenic potential human bone marrow mesenchymal stem cells hbmscs unlike bovine bone marrow interstitial fluid abif nbi
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Exact solutions for the transcritical Riemann problem of two-parameter fluids
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作者 Haotong BAI Yixin YANG +2 位作者 Wenjia XIE Dejian LI Mingbo SUN 《Applied Mathematics and Mechanics(English Edition)》 2025年第12期2385-2406,共22页
Transcritical and supercritical fluids widely exist in aerospace propulsion systems,such as the coolant flow in the regenerative cooling channels of scramjet engines.To numerically simulate the coolant flow,we must ad... Transcritical and supercritical fluids widely exist in aerospace propulsion systems,such as the coolant flow in the regenerative cooling channels of scramjet engines.To numerically simulate the coolant flow,we must address the challenges in solving Riemann problems(RPs)for real fluids under complex flow conditions.In this study,an exact numerical solution for the one-dimensional RP of two-parameter fluids is developed.Due to the comprehensive resolution of fluid thermodynamics,the proposed solution framework is suitable for all forms of the two-parameter equation of state(EoS).The pressure splitting method is introduced to enable parallel calculation of RPs across multiple grid points.Theoretical analysis demonstrates the isentropic nature of weak waves in two-parameter fluids,ensuring that the same mathematical properties as ideal gas could be applied in Newton's iteration.A series of numerical cases validate the effectiveness of the proposed method.A comparative analysis is conducted on the exact Riemann solutions for the real fluid EoS,the ideal gas EoS,and the improved ideal gas EoS under supercritical and transcritical conditions.The results indicate that the improved one produces smaller errors in the calculation of momentum and energy fluxes. 展开更多
关键词 two-parameter fluid Riemann problem(RP) exact solution supercritical fluid pressure splitting transcritical fluid
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Thermal investigation of water-based radiative magnetized micropolar hybrid nanofluid flow subject to impacts of the Cattaneo–Christov flux model on a variable porous stretching sheet with a machine learning approach
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作者 Showkat Ahmad Lone Zehba Raizah +3 位作者 Rawan Bossly Fuad SAlduais Afrah Al-Bossly Arshad Khan 《Chinese Physics B》 2025年第6期357-375,共19页
This work investigates water-based micropolar hybrid nanofluid(MHNF) flow on an elongating variable porous sheet.Nanoparticles of diamond and copper have been used in the water to boost its thermal conductivity. The m... This work investigates water-based micropolar hybrid nanofluid(MHNF) flow on an elongating variable porous sheet.Nanoparticles of diamond and copper have been used in the water to boost its thermal conductivity. The motion of the fluid is taken as two-dimensional with the impact of a magnetic field in the normal direction. The variable, permeable, and stretching nature of sheet's surface sets the fluid into motion. Thermal and mass diffusions are controlled through the use of the Cattaneo–Christov flux model. A dataset is generated using MATLAB bvp4c package solver and employed to train an artificial neural network(ANN) based on the Levenberg–Marquardt back-propagation(LMBP) algorithm. It has been observed as an outcome of this study that the modeled problem achieves peak performance at epochs 637, 112, 4848, and 344 using ANN-LMBP. The linear velocity of the fluid weakens with progression in variable porous and magnetic factors.With an augmentation in magnetic factor, the micro-rotational velocity profiles are augmented on the domain 0 ≤ η < 1.5 due to the support of micro-rotations by Lorentz forces close to the sheet's surface, while they are suppressed on the domain 1.5 ≤ η < 6.0 due to opposing micro-rotations away from the sheet's surface. Thermal distributions are augmented with an upsurge in thermophoresis, Brownian motion, magnetic, and radiation factors, while they are suppressed with an upsurge in thermal relaxation parameter. Concentration profiles increase with an expansion in thermophoresis factor and are suppressed with an intensification of Brownian motion factor and solute relaxation factor. The absolute errors(AEs) are evaluated for all the four scenarios that fall within the range 10^(-3)–10^(-8) and are associated with the corresponding ANN configuration that demonstrates a fine degree of accuracy. 展开更多
关键词 MHD fluid hybrid nanofluid Cattaneo–Christov flux model variable porous surface micropolar fluid brownian motion and thermophoresis ANN approach
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Contrast in Fluid M etallogeny between the Tianmashan Au-S Deposit and the Datuanshan Cu Deposit in Tongling,Anhui Province 被引量:2
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作者 LEE Hyun Koo 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2003年第1期116-124,共9页
A comprehensive contrast of ore-forming geological background and ore-forming fluid features, especially fluid ore-forming processes, has been performed between the Tianmashan and the Datuanshan ore deposits in Tongli... A comprehensive contrast of ore-forming geological background and ore-forming fluid features, especially fluid ore-forming processes, has been performed between the Tianmashan and the Datuanshan ore deposits in Tongling, Anhui Province. The major reasons for the formation of the stratabound skarn Au-S ore deposit in Tianmashan and the stratabound skarn Cu ore deposit in Datuanshan are analyzed in accordance with this contrast. The magmatic pluton in Tianmashan is rich in Au and poor in Cu, but that in Datuanshan is rich in Cu and Au. The wallrock strata in Tianmashan contain Au-bearing pyrite layers with some organic substance but those in Datuanshan contain no such layers. Moreover, the ore-forming fluids in Tianmashan are dominantly magmatic ones at the oxide and sulfide stages, but those with high content of Cu in Datuanshan are mainly groundwater fluids. In addition, differences in compositional evolution and physicochemical condition variation of the ore-forming fluids result in gradual dispersion 展开更多
关键词 fluid inclusion fluid ore-forming process contrast in fluid metallogeny Au-S ore deposit Cu ore deposit magmatic fluid groundwater fluid TONGLING Anhui Province
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CFD investigation in the temperature effect on coal catalytic hydrogasification in the pressurized bubbling fluidized bed 被引量:1
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作者 Yin Zhang Shuai Yan +3 位作者 Zihong Xia Caixia Chen Xuan Qu Jicheng Bi 《Chinese Journal of Chemical Engineering》 2025年第2期205-217,共13页
Temperature is a critical factor influencing the performance of coal catalytic hydrogasification in bubbling fluidized bed gasifiers.Numerical simulations at various temperatures(1023 K,1073 K,1123 K,and 1173 K)are co... Temperature is a critical factor influencing the performance of coal catalytic hydrogasification in bubbling fluidized bed gasifiers.Numerical simulations at various temperatures(1023 K,1073 K,1123 K,and 1173 K)are conducted to elucidate the mechanisms by which temperature affects bubble size,global reaction performance,and particle-scale reactivity.The simulation results indicate that bubble size increases at elevated temperatures,while H_(2)-char hydrogasification reactivity is enhanced.Particle trajectory analyses reveal that particles sized between 100 and 250μm undergo intense char hydrogasification in the dense phase,contributing to the formation of hot spots.To assess the impact of temperature on the particle-scale flow-transfer-reaction process,the dimensionless quantities of Reynolds,Nusselt,and Sherwood numbers,along with the solids dispersion coefficient,are calculated.It is found that higher temperatures inhibit bubble-induced mass and heat transfer.In general,3 MPa,1123 K,and 3-4 fluidization numbers are identified as the optimal conditions for particles ranging from 0 to350μm.These findings provide valuable insights into the inherent interactions between temperature and gas-particle reaction. 展开更多
关键词 fluidIZED-BED GASIFICATION Computational fluid dynamics
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Changes in shale microstructure and fluid flow under high temperature:Experimental analysis and fluid-structure interaction simulation 被引量:1
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作者 Xiang-Ru Chen Xin Tang +4 位作者 Rui-Gang Zhang Heng Yang Qiu-Qi Chen Zhang-Ping Yan Lei Zhang 《Petroleum Science》 2025年第4期1699-1711,共13页
Oil shale is characterized by a dense structure,low proportion of pores and fissures,and low permeability.Pore-fracture systems serve as crucial channels for shale oil migration,directly influencing the production eff... Oil shale is characterized by a dense structure,low proportion of pores and fissures,and low permeability.Pore-fracture systems serve as crucial channels for shale oil migration,directly influencing the production efficiency of shale oil resources.Effectively stimulating oil shale reservoirs remains a challenging and active research topic.This investigation employed shale specimens obtained from the Longmaxi Formation.Scanning electron microscopy,fluid injection experiments,and fluid-structure interaction simulations were used to comprehensively analyze structural changes and fluid flow behavior under high temperatures from microscopic to macroscopic scales.Experimental results indicate that the temperature has little effect on the structure and permeability of shale before 300℃.However,there are two threshold temperatures within the range of 300 to 600℃that have significant effects on the structure and permeability of oil shale.The first threshold temperature is between 300 and 400℃,which causes the oil shale porosity,pore-fracture ratio,and permeability begin to increase.This is manifested by the decrease in micropores and mesopores,the increase in macropores,and the formation of a large number of isolated pores and fissures within the shale.The permeability increases but not significantly.The second threshold temperature is between 500 and 600℃,which increases the permeability of oil shale significantly.During this stage,micropores and mesopores are further reduced,and macropores are significantly enlarged.A large number of connected and penetrated pores and fissures are formed.More numerous and thicker streamlines appear inside the oil shale.The experimental results demonstrate that high temperatures significantly alter the microstructure and permeability of oil shale.At the same time,the experimental results can provide a reference for the research of in-situ heating techniques in oil shale reservoir transformation. 展开更多
关键词 High temperature treatment Oil shale Longmaxi Formation fluidestructure interaction fluid simulation
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Trace Element Geochemistry and Sr-Nd Isotopic Characteristics of Scheelite from the Gejiu Sn-Cu-(W)Ore District:Constraints on Tungsten Sources and Evolution of W-bearing Hydrothermal Fluids
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作者 HAN Zhang LI Chao +4 位作者 CHEN Yaokun YAN Qinggao YANG Fucheng WEI Chao JIANG Xiaojun 《Acta Geologica Sinica(English Edition)》 2025年第4期1093-1104,共12页
The Gejiu tin-copper-(tungsten)(Sn-Cu-(W))polymetallic district is located in the southwest of the W-Sn metallogenic belt in the western Youjiang Basin,Yunnan,Southwest China.Abundant W minerals have been identified i... The Gejiu tin-copper-(tungsten)(Sn-Cu-(W))polymetallic district is located in the southwest of the W-Sn metallogenic belt in the western Youjiang Basin,Yunnan,Southwest China.Abundant W minerals have been identified in the region via exploration.However,metallogenic sources and evolution of W remain unclear,and the existing metallogenic model has to be updated to guide further ore prospecting.Elemental and Sr-Nd isotopic data for scheelites assist in the determination of sources and evolution of the W-mineralizing fluids and metals in the district.Based on field geological survey,the scheelites in the Gejiu district can be categorized into three types:altered granite(Type Ⅰ),quartz vein(Type Ⅱ)from the Laochang deposit,and skarn(Type Ⅲ)from the Kafang deposit.Types Ⅰ and Ⅱ scheelites have low molybdenum(Mo)and strontium(Sr)contents,and Type Ⅱ scheelite has lower Sr contents than Type Ⅰ as well as higher Mo and Sr contents than Type Ⅲ scheelites.Varying Mo contents across the scheelite types suggests that the oxygen fugacity varied during ore accumulation.Type Ⅰ and Type Ⅱ scheelites exhibit similar rare earth elements(REE)patterns;Type Ⅲ scheelite contains lower REE content,particularly HREE,compared with the other scheelites.All scheelites exhibit negative Eu anomalies in the chondrite-normalized REE patterns.As the W-mineralization and two-mica granite share close spatial and temporal relationships,the negative Eu anomalies were likely inherited from the two-mica granite.Type Ⅰ and Type Ⅱ scheelites display varied(^(87)Sr/^(86)Sr)_(82 Ma)(0.7090-0.7141)andε_(Nd)(82 Ma)(from−9.9 to−5.4)values,similar to those of granite.However,Type Ⅲ scheelite exhibits lower(^(87)Sr/^(86)Sr)_(82 Ma)(0.7083-0.7087)and lowerε_(Nd)(82 Ma)(from−10.5 to−6.9)values than the two-mica granite.This indicates that the two-mica granite alone did not provide the ore-forming fluids and metals and that the Type Ⅲ scheelite ore-forming fluids likely involved external fluids that were probably derived from carbonate rocks.The implication is that highly differentiated two-mica granites were the source of primary W-bearing metals and fluids,which is consistent with earlier research on the origin of Sn ore-forming materials. 展开更多
关键词 MINERALOGY SCHEELITE Sr-Nd isotope ore-forming fluid fluid evolution
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Laminar flow of high-viscous non-Newtonian power-law and Bingham fluids in multiple structural bifurcation channel distributors:Flow patterns and pressure drop correlation
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作者 Xiaoyi Qiu Xuesong Wang +5 位作者 Jie Jiang Yuning Zhou Wenze Guo Zhenhao Xi Ling Zhao Weikang Yuan 《Chinese Journal of Chemical Engineering》 2025年第11期140-156,共17页
This study presents a theoretical and experimental analysis of laminar flow behavior of high-viscous non-Newtonian power-law and Bingham fluids in multiple structural bifurcation channel distributors.Theoretical model... This study presents a theoretical and experimental analysis of laminar flow behavior of high-viscous non-Newtonian power-law and Bingham fluids in multiple structural bifurcation channel distributors.Theoretical models are derived to describe velocity profiles,shear rate distribution,and pressure drop across specific channels.Modified pressure drop models are proposed based on experiments on 6 kinds of non-Newtonian fluids and 3 types of bifurcation channel distributors with different transition areas.Specifically,the deviations between the theoretical models and the experimental results are systematically analyzed,and models were modified with correction coefficients based on Reynolds number and dimensionless shape factor.The theoretical results,modified results and experimental data are compared and discussed to ensure the accuracy of the modified models,demonstrating a significant improvement in the prediction of pressure drops for high-viscous non-Newtonian fluids in certain types of bifurcation channels.Additional experiments and analyses were carried out to validate the modified models and the results suggest that the models offer a certain degree of universal applicability in bifurcation channel designs.It implies that for other types of bifurcation channel distributors,similar correction methods based on Reynolds number and shape factor may also be applicable even with different coefficients. 展开更多
关键词 DISTRIBUTOR Flow resistance Pressure drop Power-law fluids Bingham fluids Laminar flow
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Trajectories of cumulative fluid balance and the association with pressure injuries in ICU patients
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作者 Xiangping Chen Peiqi Liu +5 位作者 Bingyan Zhu Xiumin Qiu Wei Yu Yuewen Lao Xiaoyan Gong Yiyu Zhuang 《International Journal of Nursing Sciences》 2025年第6期566-572,I0003,共8页
Objective:This study aimed to investigate the longitudinal trajectories of cumulative fluid balance(CFB)in intensive care unit(ICU)patients and analyze the relationship between different trajectory groups and the occu... Objective:This study aimed to investigate the longitudinal trajectories of cumulative fluid balance(CFB)in intensive care unit(ICU)patients and analyze the relationship between different trajectory groups and the occurrence of pressure injuries(PIs).Methods:In this retrospective longitudinal study,we obtained health-related data from the Medical Information Mart for Intensive Care IV database,including sociodemographic,disease-related variables,and ICU treatment variables.The daily CFB adjusted for body weight was calculated,and the occurrence of PIs during the ICU stay was recorded.A group-based trajectory model was used to explore the different CFB trajectories.Binary logistic regression was used to analyze the relationship between the CFB trajectory group and PIs.Results:Among the 4,294 included participants,we identified four distinct trajectories of CFB in ICU patients:the rapid accumulation group(12.5%),the slow accumulation group(28.5%),the neutral balance group(41.7%),and the negative decrease group(17.3%).After adjusting for some sociodemographic,disease-related variables,and ICU treatment variables,the rapid accumulation group had an OR of 1.63(95%CI:1.30,2.04)for all stages of PIs and an OR of 1.36(95%CI:1.08,1.72)for stage II or higher PIs compared to the neutral balance group.Conclusions:Four unique trajectories of CFB were identified among patients in the ICU,including rapid accumulation,slow accumulation,neutral balance,and negative decrease.Rapid accumulation independently increased the risk of PIs during ICU stay. 展开更多
关键词 Cumulative fluid balance fluid overload Intensive care unit Pressure injury TRAJECTORY
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An innovative external drainage device for suprachoroidal fluid: the puncture needle with drainage groove
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作者 Jing-Wen Hui Xiao-Li Li +2 位作者 Bo Xiao Quan-Hong Han Ying Wang 《International Journal of Ophthalmology(English edition)》 2025年第5期962-964,共3页
Dear Editor,We introduce a novel surgical instrument designed to overcome the challenges in draining fluid from the suprachoroidal space in patients with choroidal detachment.In the evolving landscape of ophthalmic su... Dear Editor,We introduce a novel surgical instrument designed to overcome the challenges in draining fluid from the suprachoroidal space in patients with choroidal detachment.In the evolving landscape of ophthalmic surgeries,procedures that were once considered complex,such as those for choroidal detachment,are becoming increasingly common.Drainage of subchoroidal fluid was derived from 1985[1]with indirect visualization during scleral buckle surgery[2-4]. 展开更多
关键词 surgical instrument scleral buckle surgery draining fluid innovative external drainage device choroidal detachmentare indirect visualization choroidal detachmentin subchoroidal fluid
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Advances and future prospects of shale oil and gas drilling fluid technology
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作者 SUN Jinsheng XU Guiqin +3 位作者 DING Yang LYU Kaihe FAN Junhao LI Jian 《Petroleum Exploration and Development》 2025年第6期1609-1623,共15页
This paper systematically reviews the advances in shale oil and gas drilling fluid technology,provides an in-depth analysis of the critical bottlenecks in each technology and explores their future development directio... This paper systematically reviews the advances in shale oil and gas drilling fluid technology,provides an in-depth analysis of the critical bottlenecks in each technology and explores their future development directions.Several technologies have been developed for shale oil and gas:water-based drilling fluids with a core emphasis on sealing,inhibition and lubrication;oil-based drilling fluids centered around wellbore strengthening,low-oil-water-ratio emulsions,and synthetic-based systems;drilling fluids for reservoir protection based on clay-free,under-balanced,and interfacial modification;as well as lost circulation control technologies founded on bridging,gelling,responsive,and composite mechanisms.A comprehensive analysis indicates that existing technologies are still plagued by several bottlenecks,including inadequate high-temperature and contamination resistance,prohibitive costs,and poor formation adaptability.Drilling operations still face severe challenges such as wellbore instability,reservoir damage and severe fluid losses.Accordingly,the following prospects for future shale oil and gas drilling fluid technology are proposed:(1)Water-based drilling fluids require a focus on the synergistic effects of nanoscale plugging and chemical inhibition,the development of smart responsive lubricants,and enhanced resistance to high temperatures and acid gas contamination.(2)Oil-based drilling fluids should achieve breakthroughs in novel emulsifiers for cost-effectiveness and high-temperature resistance,alongside intensified research efforts in environmentally friendly technologies.(3)Reservoir protective drilling fluids necessitate the development of a real-time prediction and diagnosis expert system for formation damage,coupled with the advancement and application of high-temperature resistant additives and intelligent integrated pressure control equipment.(4)Lost circulation control technologies should be dedicated to developing smart responsive plugging materials and strengthening their compatibility with fracture networks. 展开更多
关键词 shale oil and gas water-based drilling fluid oil-based drilling fluid reservoir protection lost circulation control energy security
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