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Dynamical instability of the dark state in the conversion of Bose-Fermi mixtures into stable molecules
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作者 孟少英 吴炜 +2 位作者 陈希浩 张静 傅立斌 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第8期71-76,共6页
In this paper, we investigate the dynamical instability of the dark state in the conversion of Bose-Fermi mixtures into stable molecules through a stimulated Raman adiabatic passage aided by Feshbach resonance. We ana... In this paper, we investigate the dynamical instability of the dark state in the conversion of Bose-Fermi mixtures into stable molecules through a stimulated Raman adiabatic passage aided by Feshbach resonance. We analytically obtain the regions where the dynamical instability appears and find that such instability in the Bose-Fermi mixture system is caused not only by bosonic interparticle interactions but also by Pauli blocking terms, which is different from the scenario of a pure bosonic system where instability is induced by nonlinear interparticle collisions. Taking a 40K-87Rb mixture as an example, we give the unstable regions numerically. 展开更多
关键词 bose-fermi mixture dynamical instability dark state
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Spontaneous symmetry breaking of a Bose-Fermi mixture in a two-dimensional double-well potential
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作者 Wang Yuan-Sheng Yan Pei-Gen +1 位作者 Li Bin Liu Xue-Shen 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第1期6-11,共6页
We study the spontaneous symmetry breaking of a superfluid Bose-Fermi mixture in a two-dimensional double- well potential. The mixture is described by a set of coupled Gross-Pitaevskii equations. The symmetry breaking... We study the spontaneous symmetry breaking of a superfluid Bose-Fermi mixture in a two-dimensional double- well potential. The mixture is described by a set of coupled Gross-Pitaevskii equations. The symmetry breaking phenomenon is demonstrated in the two-dimensional double-well potential in the mixture. The results are summarized in the phase diagrams of the mixture particle numbers, which are divided into symmetric and asymmetric regions by the asymmetry ratios. The dynamical pictures of the spontaneous symmetry breaking induced by a gradual transformation of the single-well potential into a double-well one are also illustrated. The properties of the quantum degenerate mixture are explored using the realistic parameters for a ^40K-^87Rb system. 展开更多
关键词 spontaneous symmetry breaking bose-fermi mixture double-well potential
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Topological properties of one-dimensional hardcore Bose-Fermi mixture
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作者 贾永飞 郭怀明 +2 位作者 秦吉红 陈子瑜 冯世平 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第9期258-262,共5页
We study the topological properties of a one-dimensional (1D) hardcore Bose-Fermi mixture using the exact diagonalization method. We firstly add a hardcore boson to a fermionic system and by examining the edge state... We study the topological properties of a one-dimensional (1D) hardcore Bose-Fermi mixture using the exact diagonalization method. We firstly add a hardcore boson to a fermionic system and by examining the edge states we find that the quasi-particle manifests the topological properties of the system. Then we study a mixture with 7 fermions and 1 boson. We find that the mixture also exhibits topological properties and its behaviors are similar to that of the corresponding fermionic system. We present a qualitative explanation to understand such behaviors using the mapping between a hardcore boson and a spinless fermion. These results show the existence of topological properties in a 1D hardcore Bose-Fermi mixture and may be realized using cold atoms trapped in optical lattices experimentally. 展开更多
关键词 bose-fermi mixture topological insulators
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Tunable Range Interactions and Multi-Roton Excitations for Bosons in a Bose-Fermi Mixture with Optical Lattices
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作者 Chao Feng Yu Chen 《Communications in Theoretical Physics》 SCIE CAS CSCD 2019年第7期869-875,共7页
In this article,we discuss a method to control the long-range interactions between bosons in a threedimensional Bose-Fermi mixture with the help of optical lattices on fermions.We find the range and the peaked momentu... In this article,we discuss a method to control the long-range interactions between bosons in a threedimensional Bose-Fermi mixture with the help of optical lattices on fermions.We find the range and the peaked momentum of the fermion-mediated interactions can be tuned by the optical lattice depth and the fermion density.If the fermion density is close to half-filling,roton excitations can be generated with weak Bose-Fermi interactions.Further,if the fermions are not exact at half-filling,multi-roton structure may emerge,implying competing density orders.Therefore,tuning the lattice depth and the fermion density in a Bose-Fermi mixture serves as an effective way to control the interaction range and resonant momentum between bosons. 展开更多
关键词 bose-fermi mixture multi-roton TUNABLE range interaction
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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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The effects of bisphenol compounds on endocrine disruption and reproductive function from epidemiological analysis to animal exposure:A mixture analysis
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作者 Peiyun Jiang Weiwei Wang +3 位作者 Jiande Li Yating Li Xiaotong Ji Huifeng Yue 《Journal of Environmental Sciences》 2026年第2期537-547,共11页
Bisphenol F(BPF)and Bisphenol S(BPS)are widely used substitutes for Bisphenol A(BPA).However,growing evidence indicated that BPF and BPS may induce physiological effects similar to those of BPA.Furthermore,chemical ma... Bisphenol F(BPF)and Bisphenol S(BPS)are widely used substitutes for Bisphenol A(BPA).However,growing evidence indicated that BPF and BPS may induce physiological effects similar to those of BPA.Furthermore,chemical management and control is primarily focus on the risk assessment of individual compounds,often overlooking the implications of chemical mixtures.We hypothesize that exposure to a mixture of BPA and its substitutes will enhance their endocrine-disruptive effects,disrupt steroid hormone homeostasis,and further impair reproductive system functionality.In the animal study,both female and male mice were exposed to 333μg/kg of BPA,BPF,BPS,their mixture(333μg/kg(MIXL),and 1 mg/kg(MIXH))via gavage daily for four weeks.The study demonstrated that bisphenols(BPs)affected the expression of genes related to steroid hormone synthesis.The MIXL group of female mice exhibited an increasing trend in estradiol(E2)levels and a decreasing trend in progesterone(Pg)and testosterone(TT)levels.Additionally,follicular development was impacted,resulting in an increased number of atretic follicles.In contrast,a significant increase in E2 concentration and disruption of testicular morphology were observed in the MIXH group of male mice,accompanied by a decline in sperm quality.Importantly,these results were corroborated by a population-based investigation.Collectively,the animal experiments indicate that mixed exposure to BPs disrupts hormone levels and adversely affects reproductive function,while epidemiological evidence further establishes correlative links between bisphenols and hormone levels.These findings underscore the necessity of considering chemical mixtures during testing and risk assessment. 展开更多
关键词 BISPHENOLS mixture exposure Animal experiments Steroid hormone synthesis Reproductive function Epidemiological studies
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Optimal orthogonal block designs for threecomponent symmetric general blending models in mixture experiment
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作者 Jiawei Bao Yu Tang 《Statistical Theory and Related Fields》 2026年第1期117-134,共18页
In mixture experiments,the observed response is determined by the relative proportions of the components,consequently rendering the experimental region a simplex.This paper focuses primarily on the optimal designs of ... In mixture experiments,the observed response is determined by the relative proportions of the components,consequently rendering the experimental region a simplex.This paper focuses primarily on the optimal designs of mixture experiments that involve process variables.Prior research has extensively delved into optimal orthogonal block designs for some classic mixture models with process variables.Based on the framework of general blending models,this paper proposes a class of symmetric linear mixture models,which can be regarded as a generalization of many existing ones.Under the orthogonal blocking conditions,orthogonal block designs are devised through Latin squares in the presence of process variables.TheD-,A-,and E-optimality criteria are utilized to obtain optimal designs at the boundary of the simplex in the case of 3 components.As the values of the exponents change,numerically derived optimal design points are presented to illustrate the pattern of their variations,and to verify the consistency of the results with previous research on some specific symmetric general blending models. 展开更多
关键词 mixture experiments general blending models optimal designs orthogonal Latin squares block designs
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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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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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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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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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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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Lattice point partition designs for experiments with mixture
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作者 LI Jun-peng LI Guang-hui ZHANG Chong-qi 《Applied Mathematics(A Journal of Chinese Universities)》 2025年第3期725-740,共16页
The upper bound on the model error will be decreased when the mean square error and the maximum distance deviation are sufficiently small in the uniform designs for mixture experiments and the design is more robust fo... The upper bound on the model error will be decreased when the mean square error and the maximum distance deviation are sufficiently small in the uniform designs for mixture experiments and the design is more robust for the model.However,the analytical expressions of MSED and MD are currently only available in the hypercube,but both types of deviations in other studies are just approximations.Although it can obtain good approximations in the low-dimensional case,the calculation will be more complicated for an experiment with more variables.Therefore,in this paper,an algorithm based on lattice point partitioning design is proposed to obtain the analytical expression of the MSED and MD in the region covered by the lattice points.Furthermore,the design’s optimality is considered and illustrated by examples under the same uniformity. 展开更多
关键词 Lattice point set D-OPTIMALITY uniform design mixture experiments
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Investigation of Combine Cycle Power Plants with Low-Grade Heat Utilization Working Methane-Hydrogen Mixtures
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作者 Mikhail Andreevich Ostrovsky Roman Evgenevich Zuikin +2 位作者 Muhammad Maaz Shaikh Daniil Vitalevich Patorkin Milyukov Igor Alexandrovich 《Journal of Environmental & Earth Sciences》 2025年第1期381-394,共14页
The Russian energy sector remains heavily reliant on thermal power plants,with gas generation accounting for approximately 66%of the installed capacity.However,the industry faces challenges such as depletion of reserv... The Russian energy sector remains heavily reliant on thermal power plants,with gas generation accounting for approximately 66%of the installed capacity.However,the industry faces challenges such as depletion of reserves,rising prices for hydrocarbons,and increasing concentrations of carbon dioxide in the atmosphere.This study focuses on developing new scientific and technical solutions to increase the efficiency and environmental safety of combined cycle power units.The research involves structural and parametric optimization of trinary cycle power plants operating on a methane-hydrogen mixture,as well as the development and optimization of turbine and heat exchange equipment for low-temperature power plants.The results show that the transition to trinary CCGT(Combine Cycle Gas Turbine)units with deep utilization and the use of hydrogen fuel can significantly reduce specific CO_(2) emissions and increase energy efficiency up to 0.21%with also increases in capacity of turbine of approximately 17 MW.The aim of this research is to calculate the efficiency,cost effectiveness and environmental-friendly solution for power generation using mixture of hydrogen-methane as fuel in combine cycle power plant that includes ORC.Additionally,the efficiency of the organic Rankine Cycle(ORC)benefits from the increased moisture,with capacity improvements of 1–2 MW observed when the hydrogen proportion rises from 25%to 50%.Moreover,the potential for zero emissions,coupled with significant increases in power output and efficiency,underscores hydrogen’s role as a pivotal component in the future of energy production. 展开更多
关键词 Low Heat Trinary Cycle Methane Hydrogen mixture Combustion
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