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ULTRAVIOLET SPECTROPHOTOMETRY OF MULTI-COMPONENT MIXTURES USING ARTIFICIAL NEURAL NETWORKS
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作者 Xin Hua SONG Jian WANG Ru Qin YU 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第12期941-944,共4页
Three—layer back—propagation neural networks were used for processing the information provided by the ultraviolet spectra of five—component mixtures, affecting the simultaneous determination of the components with ... Three—layer back—propagation neural networks were used for processing the information provided by the ultraviolet spectra of five—component mixtures, affecting the simultaneous determination of the components with satisfactory results. 展开更多
关键词 ULTRAVIOLET SPECTROPHOTOMETRY OF multi-component mixtureS USING ARTIFICIAL NEURAL NETWORKS
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Elutriation characteristics of multi-component mixtures in a fluidized bed pyrolysis process 被引量:2
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作者 Xing Wu Jingbo Peng +1 位作者 Yu Zhang Zhiduo Wang 《Particuology》 SCIE EI CAS CSCD 2021年第5期131-138,共8页
Multi-component mixtures were prepared to simulate a bed of walnut shells undergoing pyrolysis in acold fluidized bed.Four mixtures with different ratios of walnut shell,semi-chars,and clean char were used.Batch elutr... Multi-component mixtures were prepared to simulate a bed of walnut shells undergoing pyrolysis in acold fluidized bed.Four mixtures with different ratios of walnut shell,semi-chars,and clean char were used.Batch elutriation experiments using these mixtures were performed in a transparent fluidized bed to allow direct observation of the flow patterns and particle composition.The results indicated that the bubble wake rather than bubble nose was primarily responsible for particle entrainment at higher gas velocities,and that coarser particles would be“transformed”into elutriable particles.Dimensionless gas velocities ranged from 0.2 to 1.0 and an exponential decrease in particle concentration with respect to bed height was observed.The transport disengagement height(TDH)gradually increased with the gas velocity until the entire bed layer enters a pneumatic transport state.Notably,larger TDHs were required when the bed contained a larger fraction of light components.Two characteristic parameters were used to evaluate particle elutriation:the elutriation rate constant(K),and the residual volatile content of the elutriated particles(v′).These parameters were used to optimize operating gas velocity for the fluidized bed. 展开更多
关键词 Fluidized bed ELUTRIATION multi-component mixture Walnut shell PYROLYSIS
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Molecular simulation of CH_(4)/CO_(2)/N_(2)ternary mixture competitive adsorption and diffusion dynamics in tight sandstone
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作者 Shihao Xu Cheng Cao +9 位作者 Yulong Zhao Liehui Zhang Qingping Li Shouwei Zhou Shaomu Wen Yong Hu Jinbu Li Yunsheng Wei Wei Xiong Bowen Guan 《Natural Gas Industry B》 2026年第1期77-92,共16页
Injecting impure CO_(2)for enhanced gas recovery(CO_(2)-EGR)offers a dual benefit by improving natural gas extraction while enabling CO_(2)sequestration.However,the interactions between CO_(2),N_(2),and CH_(4)under re... Injecting impure CO_(2)for enhanced gas recovery(CO_(2)-EGR)offers a dual benefit by improving natural gas extraction while enabling CO_(2)sequestration.However,the interactions between CO_(2),N_(2),and CH_(4)under reservoir conditions require further investigation.This study employs Grand Canonical Monte Carlo(GCMC)and Molecular Dynamics(MD)simulations to quantify the adsorption and diffusion behaviors of CO_(2),N_(2),and CH_(4)in quartz nanopores over a pressure range of 1-24 MPa under varying water saturations and gas compositions.The results indicate that:(1)CO_(2)exhibits the broadest energy distribution and the strongest adsorption stability,occupying about 20%-30%more adsorption sites than CH_(4)or N_(2)and showing the least sensitivity to water saturation,with only a 30%reduction at 50%saturation,compared to 60%for CH_(4),giving CO_(2)a clear competitive advantage.(2)The adsorption and desorption behaviors are strongly pressure dependent,as increasing pressure reduces the adsorption layer area and shifts gas distribution from adsorption dominated to free phase.Competitive adsorption analysis reveals that while CO_(2)dominates displacement at low pressures,mixtures that contain N_(2)achieve higher CH_(4)desorption efficiency above 13 MPa by mitigating diffusion resistance.(3)A higher N_(2)fraction improves CH_(4)diffusion coefficients,thereby facilitating gas mobility and ensuring superior recovery performance under high-pressure conditions.This study advances the fundamental knowledge of microscale gas behavior in tight sandstones and supports the feasibility of impure CO_(2)injection as a practical strategy for sustainable gas production. 展开更多
关键词 Competitive adsorption Diffusion coefficient Ternary mixture Tight sandstone Molecular simulation
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Investigation of equivalent strength parameters of soil-rock mixture using numerical manifold method
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作者 Junfeng Li Yongtao Yang +2 位作者 Yang Xia Hong Zheng Shuilin Wang 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第1期637-650,共14页
As binary geological media,soil-rock mixtures(SRMs)exhibit a distinct gradational composition,leading to their unique mechanical behaviors.To appraise the stability of SRM slopes,it is essential to determine equivalen... As binary geological media,soil-rock mixtures(SRMs)exhibit a distinct gradational composition,leading to their unique mechanical behaviors.To appraise the stability of SRM slopes,it is essential to determine equivalent parameters of SRMs,which are typically obtained through experimental and numerical methods.In contrasted to other numerical methods,the numerical manifold method(NMM)is more effective in addressing SRM problems.This is because the high-precision regular mathematical meshes in NMM can be used without aligning with the soil-rock interfaces and boundaries of SRMs.In the current research,the equivalent strength parameters of SRMs,i.e.the equivalent cohesion ce and internal friction angleϕ_(e),are determined using NMM.Initially,an NMM triaxial numerical model is established and validated based on triaxial experiments.Subsequently,the soil and rock parameters are derived through parameter inversion.Moreover,the impacts of rock content,size,shape and rock blocks'major-axis orientation on ce andϕ_(e) of SRMs are thoroughly examined using the NMM triaxial numerical model.Additionally,a fitting function is proposed to linkϕ_(e) to the rock content and size of SRMs.When other influencing factors are fixed,the above fitting model leads to the following conclusions:(1)the predictedϕ_(e) of SRMs increase with the increase of rock content;and(2)SRM samples with smaller rocks display a higher predictedϕ_(e). 展开更多
关键词 Soil-rock mixtures Equivalent strength parameters Numerical manifold method
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Fatigue of Recycled Concrete Aggregate Asphalt Mixture under Temperature-Humidity Coupling
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作者 CHEN Hao ZHENG Wenhua +5 位作者 JI Jie DONG Zhilei YU Yening WANG Zihao CHEN Meng ZHOU Wenjuan 《Journal of Wuhan University of Technology(Materials Science)》 2026年第2期523-536,共14页
A comprehensive full-sieve-hole grading correction method was used to adjust aggregate gradings.The fatigue properties of recycled concrete aggregate(RCA)asphalt mixtures were investigated using an improved indirect t... A comprehensive full-sieve-hole grading correction method was used to adjust aggregate gradings.The fatigue properties of recycled concrete aggregate(RCA)asphalt mixtures were investigated using an improved indirect tensile fatigue test under temperature-humidity coupling based on 20-year meteorological data of Beijing,and the degeneration mechanism was further explored by scanning electron microscopy and energy-dispersive spectroscopy.The experimental results indicate that replacing 5-20 mm coarse limestone aggregate(LA)with RCA at a 50% substitution volume can mitigate the impact of RCA variations on the asphalt mixture proportioning design.All RCA asphalt mixtures have lower initial fatigue properties than the LA asphalt mixture.However,under temperature-humidity coupling,the long-term fatigue property of an RCA asphalt mixture with a low proportion of recycled brick exceeds that of the LA asphalt mixture,and the fatigue life decline rate of the RCA asphalt mixture during 10-year service decreases by approximately 25%.This is due to the penetration of the asphalt mortar into the RCA through the pores and cracks on the RCA surface.It forms an interfacial transition zone composed of asphalt mortar and cement mortar and further reduces the mixture damage caused by the water and freeze-thaw conditions. 展开更多
关键词 recycled concrete aggregate asphalt mixture temperature-humidity coupling fatigue property micromechanism
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Suffusion of sand-clay mixtures under stepwise increase in hydraulic gradient
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作者 Jooho Lee Yerim Yang +1 位作者 Hangseok Choi Jongmuk Won 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第2期1587-1600,共14页
Suffusion refers to the loss of fineparticles within the soil matrix without any associated volume change,induced by hydrodynamic forces.This study investigated the suffusion of sand-clay mixtures through one-dimensio... Suffusion refers to the loss of fineparticles within the soil matrix without any associated volume change,induced by hydrodynamic forces.This study investigated the suffusion of sand-clay mixtures through one-dimensional soil column experiments under a stepwise increase in hydraulic gradient(i),aiming to evaluate the critical hydraulic gradient(icrit)as a function of the size ratio between sand and clay,clay type,and ionic concentration.It was found that icrit was less than 0.1 for all sand-clay mixtures examined in this study.In addition,the lower peak concentrations of filtrated clay observed in sand-illite mixtures,compared to those of sand-kaolinite mixtures at the same level of i,suggest that illite particles are more susceptible to suffusion.Overall,the observed breakthrough curves,mass fraction of filtrated clay,volume of outflow,and total injection time presented in this study highlight the importance of considering clay type,sand-to-clay size ratio,and ionic concentration when assessing the suffusion behavior of clay-containing soils under a stepwise increase in hydraulic gradient. 展开更多
关键词 Critical hydraulic gradient Suffusion Breakthrough curve Sand-clay mixture Ionic concentration Clay mineralogy
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Influence of Geometric Parameters of Pre-Chamber on Mixture Formation in Marine Ammonia/Hydrogen Engines
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作者 Shuzhe Yan Shengli Wei +2 位作者 Yuhao Lu Yuanchen Li Yuhan Li 《哈尔滨工程大学学报(英文版)》 2026年第1期277-291,共15页
Pre-chamber ignition technology can address the issue of uneven in-cylinder mixture combustion in large-bore marine engines.The impact of various pre-chamber structures on the formation of the mixture and jet flames w... Pre-chamber ignition technology can address the issue of uneven in-cylinder mixture combustion in large-bore marine engines.The impact of various pre-chamber structures on the formation of the mixture and jet flames within the pre-chamber is explored.This study performed numerical simulations on a large-bore marine ammonia/hydrogen pre-chamber engine prototype,considering pre-chamber volume,throat diameter,the distance between the hydrogen injector and the spark plug,and the hydrogen injector angle.Compared with the original engine,when the pre-chamber volume is 73.4 ml,the throat diameter is 14 mm,the distance ratio is 0.92,and the hydrogen injector angle is 80°.Moreover,the peak pressure in the pre-chamber increased by 23.1%,and that in the main chamber increased by 46.3%.The results indicate that the performance of the original engine is greatly enhanced by altering its fuel and pre-chamber structure. 展开更多
关键词 Pre-chamber ignition Ammonia/hydrogen fuel Pre-chamber mixture formation Jet characteristics Marine engine
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Performance evaluation and optimization of emulsified asphalt cold recycled mixtures using dual-recycled RAP and RAI materials
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作者 Haibin Li Siyu He +5 位作者 Siqian Dang Anfan Shang Jianzhou Ren Qinkun Liu Dong Zhao Fayong Yang 《Journal of Road Engineering》 2026年第1期148-159,共12页
In recent years,the amount of waste generated during milling has increased dramatically,and improper disposal poses a significant environmental challenge.To mitigate environmental pollution and enhance the road perfor... In recent years,the amount of waste generated during milling has increased dramatically,and improper disposal poses a significant environmental challenge.To mitigate environmental pollution and enhance the road performance of emulsified asphalt cold recycled mixtures(ECRM),this study employed recycled asphalt pavement(RAP)and reclaimed inorganic binder stabilized aggregate(RAI)as dual recycled materials for ECRM preparation.The blending ratios of reclaimed base and surface layer mixtures significantly influence ECRM's performance,with adjusted proportions substantially improving compressive strength and dynamic modulus.Firstly,three distinct proportioning options were developed for the recycled materials.Mix designs incorporating varying RAP/RAI ratios were used to determine the optimal mix parameters:moisture content,cement dosage,and emulsified asphalt content.Subsequently,comprehensive performance evaluations were conducted through high-temperature wheel tracking tests,freeze-thaw splitting tests,uniaxial compression tests,and dynamic modulus measurements to analyze the pavement characteristics of the three ECRM formulations.Experimental results demonstrate:Compared with ECRM with a blending ratio of RAP:RAI:new aggregate=30:50:20(Option 1),the dynamic stability,freeze-thaw splitting strength ratio,compressive strength,and compressive resilient modulus of ECRM under Option 3(RAP:RAI:new aggregate=50:30:20)decreased by 31.8%,5.2%,16.4%,and 13.1%,respectively.This indicates that increasing RAP content while reducing RAI proportion enhances the tensile strength of ECRM,yet adversely affects its high-temperature stability,moisture resistance,and compressive performance.This work not only addresses the challenge of jointly utilizing asphalt pavement waste and base waste,but also provides a cost-effective and sustainable method for the stable application of milling material resources in road engineering. 展开更多
关键词 Emulsified asphalt cold recycled mixtures Recycled asphalt pavement Recycled cement-stabilized aggregate Pavement performance evaluation
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Risk factors for paternal perinatal depression in Chinese advanced maternal age couples:A regression mixture model
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作者 Xing Yin Juan Du +1 位作者 Shao-Lian Cai Xing-Qiang Chen 《World Journal of Psychiatry》 2026年第1期267-277,共11页
BACKGROUND Paternal perinatal depression(PPD)is closely associated with maternal mental health challenges,marital strain,and adverse child developmental outcomes.Despite its significant impact,PPD remains under-recogn... BACKGROUND Paternal perinatal depression(PPD)is closely associated with maternal mental health challenges,marital strain,and adverse child developmental outcomes.Despite its significant impact,PPD remains under-recognized in family-centered clinical practice.Concurrently,against the backdrop of rising rates of delayed marriage and China’s Maternity Incentive Policy,the proportion of women giving birth at an advanced maternal age is increasing.Nevertheless,research specifically examining PPD among spouses of older mothers remains critically scarce,both in China and globally.AIM To investigate PPD and its influencing factors in Chinese advanced maternal age families.METHODS This cross-sectional study included 358 participants;it was conducted among fathers of pregnant women of advanced maternal age at five hospitals in the Pearl River Delta region of China from September 2023 to June 2024.Data were collected via a general information questionnaire,the Social Support Rating Scale,and the Edinburgh Postnatal Depression Scale.Latent profile analysis and regression mixture models(RMMs)were adopted to analyze the latent PPD types and factors that influenced PPD.RESULTS The incidence of PPD was 16.48%,and three profiles were identified:Low-symptomatic(175 cases,48.89%),monophasic(140 cases,39.10%),and high-symptomatic(43 cases,12.01%).The RMM analysis revealed that first pregnancy,low income(<¥3000/month),part-time work,and a history of abnormal pregnancy were positively associated with the high-symptomatic type(P<0.05).Conversely,high subjective support and support utilization were negatively associated with the high-symptomatic type compared with the low-symptomatic type(P<0.05).Good couple relationships,high objective and subjective support,and high support utilization were negatively associated with monophasic disorder(P<0.05).CONCLUSION PPD incidence is high among Chinese fathers with advanced maternal age partners,and the characteristics of depression are varied.Healthcare practitioners should prioritize individuals with low levels of social support. 展开更多
关键词 Advanced maternal age Paternal perinatal depression Fathers’mental health Regression mixture model Advanced-age pregnancy Latent profile analysis
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Uniform design ray in the assessment of combined toxicities of multi-component mixtures 被引量:25
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作者 Shu-Shen Liu Qian-Fen Xiao +1 位作者 Jin Zhang Mo Yu 《Science Bulletin》 SCIE EI CAS CSCD 2016年第1期52-58,共7页
Multi-component mixture(MCM) is a complicated chemical system that contains a great deal of mixture rays with various mixture ratios, and each ray includes many mixtures with different concentration levels.Currently, ... Multi-component mixture(MCM) is a complicated chemical system that contains a great deal of mixture rays with various mixture ratios, and each ray includes many mixtures with different concentration levels.Currently, in combined toxicity field, almost all studies on MCM focus on the mixtures designed by the equivalenteffect concentration ratio(EECR) procedure. However, the EECR mixtures cannot represent the whole mixture system because the EECR mixtures are located on one mixture ray in concentration space formed by multiple components. In our view, some optimal experimental design such as the uniform design(UD) should be used to effectively select many representative mixture rays from the MCM system,instead of single EECR ray. The uniform design ray(UDray) integrating UD idea with fixed-ratio ray design can systematically and comprehensively measure the combined toxicity changes in the MCM system. This review introduces the operation method, construction of uniform table and corresponding usable table, and some cases of application of the UD-ray to help readers easily use UD-ray in their MCM toxicity assessment. 展开更多
关键词 Chemical mixture Uniform design Ray design mixture ratio. Concentration-responserelationship Toxicity interaction
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A micropolar mixture theory of multi-component porous media 被引量:2
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作者 黄璐 赵成刚 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2009年第5期617-630,共14页
A mixture theory is developed for multi-component micropolar porous media with a combination of the hybrid mixture theory and the micropolar continuum theory. The system is modeled as multi-component micropolar elasti... A mixture theory is developed for multi-component micropolar porous media with a combination of the hybrid mixture theory and the micropolar continuum theory. The system is modeled as multi-component micropolar elastic solids saturated with multi- component micropolar viscous fluids. Balance equations are given through the mixture theory. Constitutive equations are developed based on the second law of thermodynamics and constitutive assumptions. Taking account of compressibility of solid phases, the volume fraction of fluid as an independent state variable is introduced in the free energy function, and the dynamic compatibility condition is obtained to restrict the change of pressure difference on the solid-fluid interface. The constructed constitutive equations are used to close the field equations. The linear field equations are obtained using a linearization procedure, and the micropolar thermo-hydro-mechanical component transport model is established. This model can be applied to practical problems, such as contaminant, drug, and pesticide transport. When the proposed model is supposed to be porous media, and both fluid and solid are single-component, it will almost agree with Eringen's model. 展开更多
关键词 hybrid mixture theory MICROPOLAR multi-component deforming porous media
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Extension of Compressibility-Route Cubic Equations of State and the Radial Distribution Functions at Contact to Multi-Component Hard-Sphere Mixtures
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作者 孙久勋 金柯 +1 位作者 蔡灵仓 吴强 《Communications in Theoretical Physics》 SCIE CAS CSCD 2014年第8期290-296,共7页
The equation of state(EOS) for hard-sphere fluid derived from compressibility routes of Percus-Yevick theory(PYC) is extended. The two parameters are determined by fitting well-known virial coefficients of pure fluid.... The equation of state(EOS) for hard-sphere fluid derived from compressibility routes of Percus-Yevick theory(PYC) is extended. The two parameters are determined by fitting well-known virial coefficients of pure fluid.The extended cubic EOS can be directly extended to multi-component mixtures, merely demanding the EOS of mixtures also is cubic and combining two physical conditions for the radial distribution functions at contact(RDFC) of mixtures.The calculated virial coefficients of pure fluid and predicted compressibility factors and RDFC for both pure fluid and mixtures are excellent as compared with the simulation data. The values of RDFC for mixtures with extremely large size ratio 10 are far better than the BGHLL expressions in literature. 展开更多
关键词 CUBIC equation of state radial distribution functions at contact hard SPHERE FLUIDS mixtures multi-components
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Characteristics of catalytic destruction of dichloromethane and ethyl acetate mixture over H_(x)PO_(4)-RuO_(x)/CeO_(2) catalyst 被引量:1
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作者 Jiawen Chen Qingjie Meng +3 位作者 Feng Bi Jingkun Chen Xiaole Weng Zhongbiao Wu 《Journal of Environmental Sciences》 2025年第2期336-349,共14页
Catalytic destruction is an ascendant technology for the abatement of volatile organic compounds(VOCs)originating fromsolvent-based industrial processes.The varied composition tends to influence each VOC’s catalytic ... Catalytic destruction is an ascendant technology for the abatement of volatile organic compounds(VOCs)originating fromsolvent-based industrial processes.The varied composition tends to influence each VOC’s catalytic behavior in the reaction mixture.We investigated the catalytic destruction of multi-component VOCs including dichloromethane(DCM)and ethyl acetate(EA),as representatives from pharmaceutical waste gases,over co-supported HxPO_(4)-RuOx/CeO_(2) catalyst.A mutual inhibitory effect relating to concentrations because of competitive adsorption was verified in the binary VOCs oxidation and EA posed a more negative effect on DCM oxidation owing to EA’s superior adsorption capacity.Preferential adsorption of EA on acidic sites(HxPO_(4)/CeO_(2))promoted DCM activation on basic sites(O^(2−))and the dominating EA oxidation blocked DCM’s access to oxidation centers(RuOx/CeO_(2)),resulting in boosted monochloromethane yield and increased chlorine deposition for DCM oxidation.The impaired redox ability of Ru species owing to chlorine deposition in turn jeopardized deep oxidation of EA and its by-products,leading to increased gaseous by-products such as acetic acid originating fromEA pyrolysis.Notably,DCM at low concentration slightly promoted EA conversion at low temperatures with or without water,consistent with the enhanced EA adsorption in co-adsorption analyses.This was mainly due to that DCM impeded the shielding effect of hydrolysate deposition from rapid EA hydrolysis depending on the decreased acidity.Moreover,water benefited EA hydrolysis but decreased CO_(2) selectivity while the generated water derived from EA was likely to affect DCM transformation.This work may provide theoretical guidance for the promotion of applied catalysts toward industrial applications. 展开更多
关键词 Catalytic destruction multi-component VOCs mixture effect Interaction mechanism
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基于Mixture模型对浓缩机浓缩沉降过程的数值模拟
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作者 史贺喜 陶浩浩 +4 位作者 王娟 李同杰 马山 石晴 刘继超 《矿山工程》 2025年第6期1438-1446,共9页
针对煤泥水沉降过程复杂且难以观测的问题,本文以直径6 m中心传动式浓缩机为对象,基于Mixture多相流模型,结合Realizable k-ε湍流模型与群体平衡模型(PBM),开展了数值模拟研究。结果表明,浓缩机内部存在进口回流区、中部回流区、出口... 针对煤泥水沉降过程复杂且难以观测的问题,本文以直径6 m中心传动式浓缩机为对象,基于Mixture多相流模型,结合Realizable k-ε湍流模型与群体平衡模型(PBM),开展了数值模拟研究。结果表明,浓缩机内部存在进口回流区、中部回流区、出口回流区和上部溢流区等典型流动区域,其中中部低速回流区有利于煤泥颗粒与药剂作用。随着时间延长,颗粒逐渐向底部富集,沉降规律清晰可见。在相同工况下,开启PBM模型后颗粒沉降速度明显加快,底部堆积量增加,验证了PBM模型对絮凝过程的适用性。研究结果可为浓缩机运行调控和药剂投加优化提供理论依据。 展开更多
关键词 浓缩机 mixture模型 PBM模型 数值模拟 煤泥沉降
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Study on the variation of the permeability coefficient of soil-rock mixtures in fault zones under different stress states 被引量:1
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作者 Wenhui Tan Shuang Liang +1 位作者 Xuewen Ma Pengfei Wang 《Deep Underground Science and Engineering》 2025年第2期210-221,共12页
As the first gold mine discovered at the sea in China and the only coastal gold mine currently mined there,Sanshandao Gold Mine faces unique challenges.The mine's safety is under continual threat from its faulted ... As the first gold mine discovered at the sea in China and the only coastal gold mine currently mined there,Sanshandao Gold Mine faces unique challenges.The mine's safety is under continual threat from its faulted structure coupled with the overlying water.As the mining proceeds deeper,the risk of water inrush increases.The mine's maximum water yield reaches 15000 m3/day,which is attributable to water channels present in fault zones.Predominantly composed of soil–rock mixtures(SRM),these fault zones'seepage characteristics significantly impact water inrush risk.Consequently,investigating the seepage characteristics of SRM is of paramount importance.However,the existing literature mostly concentrates on a single stress state.Therefore,this study examined the characteristics of the permeability coefficient under three distinct stress states:osmotic,osmotic–uniaxial,and osmotic–triaxial pressure.The SRM samples utilized in this study were extracted from in situ fault zones and then reshaped in the laboratory.In addition,the micromechanical properties of the SRM samples were analyzed using computed tomography scanning.The findings reveal that the permeability coefficient is the highest under osmotic pressure and lowest under osmotic–triaxial pressure.The sensitivity coefficient shows a higher value when the rock block percentage ranges between 30%and 40%,but it falls below 1.0 when this percentage exceeds 50%under no confining pressure.Notably,rock block percentages of 40%and 60%represent the two peak points of the sensitivity coefficient under osmotic–triaxial pressure.However,SRM samples with a 40%rock block percentage consistently show the lowest permeability coefficient under all stress states.This study establishes that a power function can model the relationship between the permeability coefficient and osmotic pressure,while its relationship with axial pressure can be described using an exponential function.These insights are invaluable for developing water inrush prevention and control strategies in mining environments. 展开更多
关键词 permeability coefficient rock block percentage sensitivity analysis soil-rock mixture stress state
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Analyzing structural changes induced by gas migration in heterogeneous pellet/powder bentonite mixtures through X-ray computed micro-tomography
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作者 Mohammed Zaidi Nadia Mokni +1 位作者 Magdalena Dymitrowska Kui Liu 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第5期3198-3212,共15页
Understanding the mechanisms of gas transport and the resulting preferential pathways formation through bentonite-based barriers is essential for their performance evaluation.In this experimental study,gas migration w... Understanding the mechanisms of gas transport and the resulting preferential pathways formation through bentonite-based barriers is essential for their performance evaluation.In this experimental study,gas migration within a heterogenous mixture of MX80 bentonite pellets and powder with a ratio of 80/20 in dry mass was investigated.A novel X-ray transparent constant volume cell has been developed to assess the effect of gas pressure,material heterogeneities,and water vapor gas saturation on breakthrough pressure and gas pathways.The new cell allows to perform high-resolution X-ray computed micro-tomography(X-ray μCT)scans to track microstructural changes during different phases of saturation and gas injection.Experimental results showed that the gas breakthrough occurred when the pressure was raised to 3 MPa.This is slightly higher than the expected swelling pressure(2.9 MPa)of the bentonite sample.Each gas injection was followed by a long resaturation phase restoring material homogeneity at μCT resolution scale(16 mm).However,the elapsed time needed for gas to breakthrough at 3 MPa diminished at each subsequent injection test.X-ray μCT results also revealed the opening of the specimen/cell wall interface during gas passage.This opening expanded as the injection pressure increased.The gas flow along the interface was associated with the development of dilatant pathways inside the sample,although they did not reach the outlet surface.It was observed that the water vapor gas saturation had no effect on the breakthrough pressure.These findings enhance the understanding of the complex mechanisms underlying microstructural evolution and gas pathway development within the highly heterogeneous mixture.The experimental outcomes highlight the effectiveness of X-ray μCT to improve quality protocols for engineering design and safety assessments of engineered barriers. 展开更多
关键词 Bentonite pellet-powder mixture Gas migration Breakthrough pressure Gas pathways X-ray computed tomography Heterogenous bentonite mixture
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Novel multi-component synergistic bioink that balances biocompatibility and mechanical strength for cartilage regeneration
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作者 Zijun MA Wendan JIA +5 位作者 Xiaoyuan WANG Rong CHENG Lu HAN Meng LI Xiaoning YANG Shengbo SANG 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 2025年第12期1156-1171,共16页
Hydrogels,owing to their porous network structure resembling the extracellular matrix(ECM),have become essential scaffold materials in the field of cartilage tissue engineering.Among them,gelatin methacrylate(GelMA)hy... Hydrogels,owing to their porous network structure resembling the extracellular matrix(ECM),have become essential scaffold materials in the field of cartilage tissue engineering.Among them,gelatin methacrylate(GelMA)hydrogels are widely used in bioink development due to their excellent biocompatibility,biodegradability,and tunable photo-crosslinking properties.However,the high biocompatibility of pure GelMA often comes at the cost of mechanical strength,limiting its applicability in cartilage regeneration.To overcome this trade-off,this study developed composite bioinks based on GelMA,silk fibroin(SF),and polyethylene oxide(PEO)for fabricating porous hydrogel scaffolds,which were then systematically characterized in terms of morphology,porosity,hydrophilicity,mechanical strength,rheological behavior,printability,and cytocompatibility.In this design,PEO serves as a porogen to generate highly porous structures(porosity up to 88%),while SF compensates for the mechanical loss caused by PEO,enabling the scaffold to retain a compression strength of up to 29.10 kPa.Among the tested formulations,the 10%GelMA/1%SF/1.5%PEO(1%=0.01 g/mL)bioink exhibited excellent printability,mechanical integrity,and cytocompatibility,and it supported a robust deposition of collagenⅡand aggrecan by chondrocytes after printing.This work provides a versatile strategy for balancing the biocompatibility and mechanical robustness in bioinks,offering a promising platform for next-generation cartilage tissue engineering scaffolds. 展开更多
关键词 Silk fibroin Polyethylene oxide multi-component collaboration Cartilage regeneration Tissue engineering
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Multi-component decompositions,linear superpositions,and new nonlinear integrable coupled KdV-type systems
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作者 Xiazhi Hao S Y Lou 《Communications in Theoretical Physics》 2025年第2期1-12,共12页
In the realm of nonlinear integrable systems,the presence of decompositions facilitates the establishment of linear superposition solutions and the derivation of novel coupled systems exhibiting nonlinear integrabilit... In the realm of nonlinear integrable systems,the presence of decompositions facilitates the establishment of linear superposition solutions and the derivation of novel coupled systems exhibiting nonlinear integrability.By focusing on single-component decompositions within the potential BKP hierarchy,it has been observed that specific linear superpositions of decomposition solutions remain consistent with the underlying equations.Moreover,through the implementation of multi-component decompositions within the potential BKP hierarchy,successful endeavors have been undertaken to formulate linear superposition solutions and novel coupled Kd V-type systems that resist decoupling via alterations in dependent variables. 展开更多
关键词 integrable system single-component decomposition multi-component decomposition linear superposition integrable coupled KdV-type system
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A facile high-efficiency preparation strategy for Al-containing multi-component boride microcrystals with superior comprehensive performance
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作者 Yong Fan Jinfeng Nie +7 位作者 Zhigang Ding Yujing Zhang Xiang Chen Wei Liu Sen Yang Sida Liu Xiangfa Liu Yonghao Zhao 《Journal of Materials Science & Technology》 2025年第1期190-203,共14页
Multi-component transition group metal borides(MMB_(2))have become a research hotspot due to their new composition design concepts and superior properties compared with conventional ceramics.Most of the current method... Multi-component transition group metal borides(MMB_(2))have become a research hotspot due to their new composition design concepts and superior properties compared with conventional ceramics.Most of the current methods,however,are complicated and time-consuming,the mass production remains a chal-lenge.Herein,we proposed a new high-efficiency strategy for synthesis of MMB_(2)using molten aluminum as the medium for the first time.The prepared Al-containing multi-component borides(TiZrHfNbTa)B_(2)microcrystals had a homogeneous composition with a hexagonal AlB_(2)structure and ultra-high hardness value of∼35.3 GPa,which was much higher than data reported in the literature and the rule of mix-ture estimations.Furthermore,combined with the First-principles calculation results,we found that the Poisson’s ratio(v)values exhibit a clearly ascending trend from 0.17 at VEC=3.5 to 0.18 at VEC=3.4,then to 0.201 at VEC=3.2 with the increasing of Al content.This indicates that the intrinsic toughness of multi-component boride microcrystals is obviously enhanced by the trace-doped Al elements.Besides,the fabricated Al-containing multi-component boride microcrystals have superior oxidation activation en-ergy and structural stability.The enhanced oxidation resistance is mainly attributed to the formation of a protective Al2 O3 oxide layer and the lattice distortion,both of which lead to sluggish diffusion of O_(2).These findings propose a new unexplored avenue for the fabrication of MMB_(2)materials with supe-rior comprehensive performance including ultra-hardness and intrinsically improved thermo-mechanical properties. 展开更多
关键词 multi-component borides First-principles calculations Crystal growth Mechanical properties Oxidation behavior
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Optimization of Extraction Process of Qingdu Jianpi Mixture by Orthogonal Experimental Design
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作者 Jiangcun WEI Bing QING +4 位作者 Jinqing PENG Xiaofen FENG Weiwei CHEN Wen ZHONG Zujie QIN 《Medicinal Plant》 2025年第3期10-14,共5页
[Objectives]To optimize the optimal extraction process of Qingdu Jianpi Mixture.[Methods]Taking water addition ratio,extraction time and extraction times as process investigation factors,psoralen content,astilbin cont... [Objectives]To optimize the optimal extraction process of Qingdu Jianpi Mixture.[Methods]Taking water addition ratio,extraction time and extraction times as process investigation factors,psoralen content,astilbin content and dry extract yield as evaluation indicators,the main influencing factors and level range of the extraction process of Qingdu Jianpi Mixture were determined on the basis of single factor test method,and the optimal weight coefficient was screened by AHP-entropy method mixed with weighting method.Combined with L_(9)(3^(4))orthogonal experiment,the best extraction process was obtained.At the same time,thin-layer chromatographic identification was used to identify Ficus simplicissima Lour.and Smilax glabra Roxb.in the medicinal liquid.[Results]The best extraction process:add 1:12 water to the prescription decoction pieces,extract under reflux for 2 times,1.5 h per time,and combine the filtrate to 250 mL.Thin layer chromatography analysis showed that the spots of Ficus simplicissima Lour.and Smilax glabra Roxb.in the medicinal solution were the same as those of reference substances at the corresponding positions,and the negative control had no interference.[Conclusions]The experimental method is reasonable and feasible,and the process is reliable,which can provide experimental reference for the subsequent application of in-hospital preparations and research and development of Qingdu Jianpi Mixture. 展开更多
关键词 Qingdu Jianpi mixture AHP-entropy method ORTHOGONAL design EXTRACTION PROCESS
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