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On transition of type V interaction in double-wedge flow with non-equilibrium effects
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作者 Wentao Xiong Yujian Zhu Xisheng Luo 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2016年第6期282-285,共4页
The transition between regular reflection (RR) and Mach reflection (MR) of type V shock-shock interaction on a double-wedge geometry with high temperature non-equilibrium effects is investigated by extended shock-... The transition between regular reflection (RR) and Mach reflection (MR) of type V shock-shock interaction on a double-wedge geometry with high temperature non-equilibrium effects is investigated by extended shock-polar method and numerical simulation. First, the critical angles of transition from detachment criterion and yon Neumann criterion are determined by the extended shock-polar method considering the non-equilibrium effects. Then wave patterns and the transition process are numerically obtained. Results of the critical transition angles from shock-polar calculation and numerical simulation show evident disagreement, indicating transition mechanism between RR and MR of type V interaction is changed. By comparing with the frozen counterpart, it is also found that non-equilibrium effects lead to a larger critical wedge angle and a larger hysteresis interval. 展开更多
关键词 Shock interaction Non-equilibrium effects Shock polar Hypersonic flow
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Impacts of Green Landscapes of Urban Freeway on Driver's Visual Perception:An Equilibrium Effect of Greenness and Complexity
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作者 Annebella Tsz Ho CHOI Ao ZHU +5 位作者 Lan LUO Jibo HE Gunwoo KIM Pongsakorn SUPPAKITTPAISARN Xiping ZHONG Bin JIANG 《景观设计学(中英文)》 2025年第6期4-24,共21页
While green landscapes are known to influence drivers'visual attention,the optimal configurations for enhancing driving safety and performance remain unclear.This study employed eyetracking technology to investiga... While green landscapes are known to influence drivers'visual attention,the optimal configurations for enhancing driving safety and performance remain unclear.This study employed eyetracking technology to investigate eye fixation and gaze behaviors of 24 drivers during a 90-minute simulated urban highway driving task across six distinct landscape conditions across three primary Areas of Interest(AOIs).Within-subject analysis of variance(ANOVA)comparing barren,turf,and woody landscapes revealed that increased greenness significantly directs drivers'eye movements towards greenery.Comparative analysis of the six landscape conditions suggested that shrub landscape settings achieved the most balanced distribution of visual attention across AOls,preventing drivers from excessively focusing on either natural or artificial features.Moreover,the ANOVA examining two shrub settings and two tree settings revealed a trade-off effect between landscape greenness and complexity.This study provides crucial empirical evidence for a balanced configuration of greenness and complexity in landscape design,confirming its critical role in achieving optimal visual perception outcomes.Finally,it proposes a triangular theoretical framework linking visual perception,mental states,and driving performance,offering theoretical support and practical reference for future research and design of healthy and safe driving environments. 展开更多
关键词 FREEWAY Green Space Curbside Landscape Visual Perception Eye Movement equilibrium effect Driving Simulation
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First-principles investigation of the concentration effect on equilibrium fractionation of Ca isotopes in forsterite 被引量:2
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作者 Yahui Song Yonghui Li +1 位作者 Wenzhong Wang Zhongqing Wu 《Acta Geochimica》 EI CAS CSCD 2019年第4期497-507,共11页
Previous theoretical studies have found that the concentration variations within a certain range have a prominent effect on inter-mineral equilibrium isotope fractionation(10^3 lna).Based on the density functional the... Previous theoretical studies have found that the concentration variations within a certain range have a prominent effect on inter-mineral equilibrium isotope fractionation(10^3 lna).Based on the density functional theory,we investigated how the average Ca–O bond length and the reduced partition function ratios(10^3 lnb)and103lna of 44 Ca/40 Ca in forsterite(Fo)are affected by its Ca concentration.Our results show that Ca–O bond length in forsterite ranges from 2.327 to 2.267 A with the Ca/(Ca+Mg)varying between a narrow range limited by an upper limit of 1/8 and a lower limit of 1/64.However,outside this narrow range,i.e.,Ca/(Ca+Mg)is lower than1/64 or higher than 1/8,Ca–O bond length becomes insensitive to Ca concentration and maintains to be a constant.Because the 10^3 lnb is negatively correlated with Ca–O bond length,the 10^3lnb significantly increases with decreasing Ca/(Ca+Mg)when 1/64<Ca/(Ca+Mg)<2/16.As a consequence,the 10^3lna between forsterite and other minerals also strongly depend on the Ca content in forsterite.Combining previous studies with our results,the heavier Ca isotopes enrichment sequence in minerals is:forsterite[orthopyroxene[clinopyroxene[calcite & diopside[dolomite[aragonite.Olivineand pyroxenes are enriched in heavier Ca isotope compared to carbonates.The 10^3lna between forsterite with a Ca/(Ca+Mg)of 1/64 and clinopyroxene(Ca/Mg=1/1,i.e.,diopside)is up to^0.64%at 1200 K.The large 103lnaFodiopsiderelative to the current analytical precision for Ca isotope measurements suggests that the dependence of10^3 lnaFo-diopsideon temperature can be used as a thermometer,similar to the one based on the 103lna of 44 Ca/40 Ca between orthopyroxene and diopside.These two Ca isotope thermometers both have a precision approximate to that of elemental thermometers and provide independent constraints on temperature. 展开更多
关键词 Ca ISOTOPE FIRST-PRINCIPLES CALCULATIONS FORSTERITE Concentration effect equilibrium ISOTOPE FRACTIONATION
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Salt effect on the liquid–liquid equilibrium of the ternary (water + phenol + methyl isobutyl ketone) system: Experimental data and correlation 被引量:1
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作者 Yun Chen Kangning Xiong +3 位作者 Shuai Shen Huimin Wang Shaoming Zhou Libo Li 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第1期168-173,共6页
The effects of NaCl, KCl and Na_2SO_4 on the liquid–liquid equilibrium(LLE) data for the ternary system, water+ phenol + methyl isobutyl ketone, were determined at 0.101 MPa and 333.15 K and 343.15 K.The nonrandom tw... The effects of NaCl, KCl and Na_2SO_4 on the liquid–liquid equilibrium(LLE) data for the ternary system, water+ phenol + methyl isobutyl ketone, were determined at 0.101 MPa and 333.15 K and 343.15 K.The nonrandom two-liquid(NRTL) model was used to correlate the experimental data and to yield corresponding binary interaction parameters for these salt containing systems.The Hand and Othmer–Tobias equations were used to confirm the dependability of the determined LLE data in this work.Distribution coefficient and selectivity were used to evaluate the extraction performance of methyl isobutyl ketone with the existence of salt.The magnitude of salt effect on the water + phenol + methyl isobutyl ketone(MIBK) system is in the following order: Na_2SO_4>NaCl>KCl. 展开更多
关键词 LIQUID-LIQUID equilibrium Methyl ISOBUTYL KETONE Salt effect PHENOL
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Salting-out effect of ionic liquids on isobaric vapor-liquid equilibrium of acetonitrile-water system
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作者 方静 赵蕊 +2 位作者 王辉 李春利 刘婧 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第8期1369-1373,共5页
This paper presents the vapor–liquid equilibrium(VLE) data of acetonitrile–water system containing ionic liquids(ILs) at atmospheric pressure(101.3 k Pa). Since ionic liquids dissociate into anions and cations, the ... This paper presents the vapor–liquid equilibrium(VLE) data of acetonitrile–water system containing ionic liquids(ILs) at atmospheric pressure(101.3 k Pa). Since ionic liquids dissociate into anions and cations, the VLE data for the acetonitrile + water + ILs systems are correlated by salt effect models, Furter model and improved Furter model. The overall average relative deviation of Furter model and improved Furter model is 5.43% and 4.68%, respectively. Thus the salt effect models are applicable for the correlation of IL containing systems. The salting-out effect theory can be used to explain the change of relative volatility of acetonitrile–water system. 展开更多
关键词 Salting-out effect Vapor–liquid equilibrium Separation Ionic liquid Acetonitrile
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Fiscal Policy Effect Analysis Based on Agents Response Equilibrium (ARE) Model 被引量:1
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作者 肖潇 胡兆光 段炜 《Journal of Donghua University(English Edition)》 EI CAS 2012年第1期62-65,共4页
Agents response equilibrium (ARE) model has been taken advantage of to build a multi-agent system for analyzing fiscal policy effect. Through establishing various types of economic entities and endowing them with abil... Agents response equilibrium (ARE) model has been taken advantage of to build a multi-agent system for analyzing fiscal policy effect. Through establishing various types of economic entities and endowing them with abilities to react and make decision, the whole system will evolve to new conditions in response to policy change. Compared with different scenarios, it can be concluded that when raising taxation ratio, sectoral scale will shrink to some extent. But supported by government expenditure, certain sectors could be kept in comparatively larger production scale. 展开更多
关键词 agents response equilibrium (ARE) model agent fiscal policy economic system policy effect
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Catalytic Effect of Activated Carbon and Activated Carbon Fiber in Non-Equilibrium Plasma-Based Water Treatment 被引量:2
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作者 张延宗 郑经堂 +2 位作者 曲险峰 于维钊 陈宏刚 《Plasma Science and Technology》 SCIE EI CAS CSCD 2008年第3期358-362,共5页
Catalysis and regeneration efficiency of granular activated carbon (GAC) and activated carbon fiber (ACF) were investigated in a non-equilibrium plasma water treatment reactor with a combination of pulsed streamer... Catalysis and regeneration efficiency of granular activated carbon (GAC) and activated carbon fiber (ACF) were investigated in a non-equilibrium plasma water treatment reactor with a combination of pulsed streamer discharge and GAC or ACF. The experimental results show that the degradation efficiency of methyl orange (MO) by the combined treatment can increase 22% (for GAC) and 24% (for ACF) respectively compared to pulsed discharge treatment alone, indicating that the combined treatment has a synergetic effect. The MO degradation efficiency by the combined treatment with pulsed discharge and saturated GAC or ACF can increase 12% and 17% respectively compared to pulsed discharge treatment alone. Both GAC and ACF show catalysis and the catalysis of ACF is prominent. Meanwhile, the regeneration of GAC and ACF are realized in this process. When H202 is introduced into the system, the utilization efficiency of ozone and ultraviolet light is improved and the regeneration efficiency of GAC and ACF is also increased. 展开更多
关键词 non-equilibrium plasma water treatment activated carbon activated carbon fiber catalytic effect
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基于风雷软件的非定常非线性耦合本构关系模型
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作者 杨俊沅 曾舒华 +4 位作者 赵文文 张砚岚 安家琦 孙傲 陈伟芳 《空气动力学学报》 北大核心 2026年第3期155-165,共11页
为实现跨流域非平衡流动的高效模拟,本文基于国家数值风洞的风雷(PHengLEI)开源框架,设计开发了非线性耦合本构关系(nonlinear coupled constitutive relations,NCCR)模型求解器PHengLEI-NCCR,并进一步构建了非定常非线性耦合本构关系模... 为实现跨流域非平衡流动的高效模拟,本文基于国家数值风洞的风雷(PHengLEI)开源框架,设计开发了非线性耦合本构关系(nonlinear coupled constitutive relations,NCCR)模型求解器PHengLEI-NCCR,并进一步构建了非定常非线性耦合本构关系模型(ALE-NCCR)。新模型有效拓展了风雷软件在连续-稀薄跨流域流动中的计算能力和适用范围,并对其在典型算例中的计算准确性进行了系统验证。首先给出了PHengLEI-NCCR求解器中涉及的控制方程、无量纲化和迭代计算策略。随后,通过ALE-NCCR求解器计算了HBS(hyper ballistic shape)模型的俯仰振荡的静、动导数。结果表明:在连续流域,PHengLEI-NCCR求解器的计算结果与实验数据具有良好一致性;在稀薄流域,PHengLEI-NCCR求解器较传统的纳维-斯托克斯-傅里叶(Navier–Stokes–Fourier,NSF)方程能够更准确地捕捉非平衡效应,与DSMC结果更为接近。此外,ALE-NCCR模型在连续流条件下可回归于ALE-NSF方程的时间精度与物理可靠性,充分证明了新模型的跨流域适用性与非定常动边界模拟能力。 展开更多
关键词 非线性耦合本构关系 跨流域流动 风雷软件 非定常流动 稀薄非平衡效应
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氯离子、硫酸根离子和硝酸根离子对三价铁离子水解平衡影响的文献综述
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作者 张前勇 李桂新 《化学教育(中英文)》 北大核心 2026年第7期102-110,共9页
2024年高中化学教材将“氯化铁水解探究实验”修订为“硫酸铁水解探究实验”,通过综述国内外文献,探讨了氯离子和硫酸根离子对三价铁离子水解平衡的影响机制。研究发现:氯离子通过配位作用抑制三价铁离子的水解,并因形成黄色配合物导致... 2024年高中化学教材将“氯化铁水解探究实验”修订为“硫酸铁水解探究实验”,通过综述国内外文献,探讨了氯离子和硫酸根离子对三价铁离子水解平衡的影响机制。研究发现:氯离子通过配位作用抑制三价铁离子的水解,并因形成黄色配合物导致溶液显色异常,干扰实验现象的直观观察;而硫酸根离子虽然配位能力更强,但其配合物颜色较浅(几乎无色),且能促进三价铁离子的沉淀。因此,选用硫酸铁替代氯化铁可规避显色干扰,更符合教学观察与实验设计的需求。本研究为教材修订提供了理论依据,并深化了对阴离子影响三价铁离子水解行为的认识。 展开更多
关键词 三价铁离子 水解平衡 配位作用 阴离子影响
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非平衡堆载作用下基坑降水开挖地表沉降的空间效应
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作者 梁新欢 迟民良 +3 位作者 何小辉 王安华 徐长节 杨开放 《土木与环境工程学报(中英文)》 北大核心 2026年第2期121-129,共9页
为研究非平衡堆载作用下地铁基坑降水开挖过程中不同特征剖面处地表沉降的空间效应特性,以南昌市某地铁车站基坑工程为背景,利用PLAXIS 3D建立三维数值模型进行模拟,模拟值与实测值吻合良好,验证了数值模拟的准确性。通过改变非平衡堆... 为研究非平衡堆载作用下地铁基坑降水开挖过程中不同特征剖面处地表沉降的空间效应特性,以南昌市某地铁车站基坑工程为背景,利用PLAXIS 3D建立三维数值模型进行模拟,模拟值与实测值吻合良好,验证了数值模拟的准确性。通过改变非平衡堆载大小和降水开挖工况,研究狭长基坑在分步降水开挖与一次性降水开挖情况下不同堆载作用对坑外地表沉降的影响规律,并进一步探讨坑外不同特征剖面地表沉降的空间效应特性。结果表明:受非平衡堆载影响,近堆载侧地表沉降大于远堆载侧;相较于一次性降水开挖工况,分步降水开挖工况下坑外各特征剖面处地表沉降值均更小;两种降水开挖工况下,非平衡堆载均弱化了近堆载侧地表沉降的空间效应,而对远堆载侧地表沉降空间效应的影响则相反,这与非平衡堆载和分段分层开挖的共同作用有关。 展开更多
关键词 基坑降水 地表沉降 空间效应 非平衡堆载 数值模拟
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返回舱再入高温流场辐射特性研究
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作者 刘向阳 田川 +2 位作者 段毅 刘元春 苗萌 《宇航学报》 北大核心 2026年第2期480-494,共15页
基于地球大气物理化学模型,通过求解带辐射源项的热化学非平衡Navier-Stokes方程,对Fire-Ⅱ返回舱再入过程中高温流场的辐射特性进行研究,分析气体辐射与非平衡流场耦合求解对流动和辐射特性的影响。结果表明,耦合计算对流场密度、温度... 基于地球大气物理化学模型,通过求解带辐射源项的热化学非平衡Navier-Stokes方程,对Fire-Ⅱ返回舱再入过程中高温流场的辐射特性进行研究,分析气体辐射与非平衡流场耦合求解对流动和辐射特性的影响。结果表明,耦合计算对流场密度、温度、组分等物理量的分布以及辐射特性有显著影响。在前体,耦合计算使得流场的平动温度降低、密度升高,脱体激波更靠近壁面;在尾迹区,振动温度分布规律因耦合计算发生显著变化。耦合计算条件下,尾迹分离涡外侧剪切层对辐射的强吸收效应使得该区域振动温度突升。耦合计算还使得流场电离程度降低,N+、O+和自由电子的数密度较非耦合计算有所下降。流场组分、温度、密度的改变,使得耦合计算得到的热辐射强度大幅低于非耦合计算结果。同时,对尾迹流场的光辐射特性进行了分析;结果表明,尾迹流场光辐射强度与波段、方向密切相关。本文通过分析返回舱再入过程中辐射-流动耦合求解对辐射特性的影响,为热防护系统和光环境的设计提供了关键参考。 展开更多
关键词 返回舱 热化学非平衡效应 高温气体辐射 尾流场光辐射特性
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税优型个人养老金增大还是减小了收入差距?——基于共同富裕视角
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作者 马笑月 周延 《中央财经大学学报》 北大核心 2026年第1期61-77,共17页
完善分配制度是妥善解决收入差距问题、促进共同富裕的必然手段。为探究税优型第三支柱个人养老金政策对收入分配的影响,本文从共同富裕视角出发,区分中高收入群体与低收入群体,构建两期动态一般均衡模型,探讨个人养老金政策对于收入差... 完善分配制度是妥善解决收入差距问题、促进共同富裕的必然手段。为探究税优型第三支柱个人养老金政策对收入分配的影响,本文从共同富裕视角出发,区分中高收入群体与低收入群体,构建两期动态一般均衡模型,探讨个人养老金政策对于收入差距的影响。研究发现,第三支柱个人养老金缴费率以及收益率的提升会恶化收入分配与再分配状况;而适当提高领取税率则可能改善收入再分配状况。进一步研究发现,第三支柱个人养老金缴费率对于收入分配与再分配的影响最大,收益率次之。基于上述结论,本文提出差异化税收模式等政策建议,旨在降低低收入群体提取养老金时的税收负担,同时保留对高收入群体养老金收入的适度调节,从而在提升制度公平性的同时,兼顾财政可持续性。 展开更多
关键词 税优型个人养老金 经济效应 一般动态均衡 收入差距
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均质非饱和黏土地层盾构隧道极限支护力计算方法
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作者 王道远 张高翔 +7 位作者 贺少辉 武薇 陈宇博 刘承宏 马济文 宋宝禄 袁金秀 刘勇 《交通运输工程学报》 北大核心 2026年第1期247-256,共10页
针对非饱和黏土地层盾构隧道极限支护力不易准确确定的难题,采用理论推导和工程算例分析相结合的方法系统研究了均质非饱和黏土地层盾构隧道开挖面支护力计算方法。考虑地层非垂直滑裂面形态、土体基质吸力作用、不完全土拱效应及主应... 针对非饱和黏土地层盾构隧道极限支护力不易准确确定的难题,采用理论推导和工程算例分析相结合的方法系统研究了均质非饱和黏土地层盾构隧道开挖面支护力计算方法。考虑地层非垂直滑裂面形态、土体基质吸力作用、不完全土拱效应及主应力偏转特性,构建了考虑多因素耦合的竖向土压力解析模型;基于极限平衡楔形体模型,进一步推演构建了开挖面支护力计算方法;结合工程算例探讨了关键参数对支护力的影响规律。研究结果表明:土拱效应引发土体竖向应力非线性演化,随埋深增加呈现先陡增后增速趋缓规律;隧顶土体竖向应力与滑裂面角度、饱和度正相关,与黏聚力、拱顶位移负相关;高饱和度条件下,推荐计算方法与规范计算结果具有高度一致性,且二者所得结果均明显高于太沙基理论预测值,偏差幅度最高可达50%;随饱和度降低,推荐解渐趋接近太沙基理论解,饱和度变化引发的松动土压力波动幅度可达30%;开挖面极限支护力受内摩擦角、黏聚力及饱和度多参数耦合影响,其中地层饱和度为关键控制因素,其差异可导致支护力变化幅度超50%。 展开更多
关键词 隧道工程 盾构隧道 极限平衡法 非饱和黏土 不完全土拱效应 开挖面极限支护力 楔形体模型
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真实气体效应下飞行/喷流参数对逆向喷流减阻降热特性的影响
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作者 杜佳宝 吴锦水 段润泽 《空气动力学学报》 北大核心 2026年第1期96-108,共13页
高速飞行器飞行时会产生大量的气动阻力和气动热,周围气体分子的振动能和电子能被激发,并发生离解和电离等化学反应,真实气体效应不可忽略。逆向喷流技术作为一种主动热防护技术,已受到广泛关注,因此有必要对真实气体效应下的逆向喷流... 高速飞行器飞行时会产生大量的气动阻力和气动热,周围气体分子的振动能和电子能被激发,并发生离解和电离等化学反应,真实气体效应不可忽略。逆向喷流技术作为一种主动热防护技术,已受到广泛关注,因此有必要对真实气体效应下的逆向喷流减阻降热特性进行深入研究。本文基于数值计算方法,对比了不同气体模型下逆向喷流系统的性能,发现热化学非平衡气体模型对钝体阻力与热流的预测更为准确,更适用于高速飞行器的气动热环境分析。采用二维可压缩Navier-Stokes方程和热化学非平衡气体模型模拟了钝体在不同飞行条件下喷流系统的流场分布,研究了真实气体效应下飞行/喷流参数对喷流流场结构、钝体气动阻力和气动热的影响。结果表明:飞行马赫数增大,钝体的总阻力和总热流显著增加,飞行马赫数从8增大到12,钝体的总阻力系数提高了29.30%,总热流增大了8.53倍。飞行攻角为10°时,迎风面和背风面的壁面压力相差2.57倍,最大热流密度相差16.17倍。增大飞行高度会降低来流总压,使喷流穿透能力增强,飞行高度从32 km增加到36 km,钝体峰值压力降低了36.34 kPa,峰值热流密度降低了1.32 MW/m_(2)。增大喷流压比对降低钝体总阻力和总热流具有显著效果,当喷流压比为0.014时,系统减阻降热效果最佳,总阻力系数和总热流相较无喷流时分别降低41.32%和73.55%。喷流温度变化主要影响近壁面温度分布,温度升高虽对钝体总阻力系数影响甚微,但会提高钝体总热流,导致系统减阻降热效率降低。 展开更多
关键词 逆向喷流 真实气体效应 减阻 降热 热化学非平衡气体模型 热防护
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考虑空间土拱效应的非饱和地层圆形基坑围护结构侧向土压力计算方法
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作者 徐杰 张振光 李海祥 《岩土力学》 北大核心 2026年第1期245-254,共10页
为合理描述非饱和地层圆形基坑围护结构侧向土压力沿深度的大小、分布、合力及作用点高度,基于非饱和土的吸应力理论与极限平衡法,首先推导了对吸应力均匀/线性分布都适用的围护结构后方土体滑动面倾角,然后组合竖向土拱和环向土拱的不... 为合理描述非饱和地层圆形基坑围护结构侧向土压力沿深度的大小、分布、合力及作用点高度,基于非饱和土的吸应力理论与极限平衡法,首先推导了对吸应力均匀/线性分布都适用的围护结构后方土体滑动面倾角,然后组合竖向土拱和环向土拱的不同作用,建立了空间土拱效应下非饱和地层圆形基坑围护结构侧向土压力的计算方法,并对比已有理论解答和模型试验数据进行验证、分析相关因素的影响规律。研究结果表明:计算方法不仅与文献理论解答、模型试验数据吻合良好,验证了其准确性和合理性,而且有效解决了非饱和地层、空间土拱效应、结构-土体接触参数等对圆形基坑侧向土压力的综合影响,有助于实现圆形基坑的设计与施工优化,具有一定的理论意义和良好的应用前景;基坑侧向土压力合力随着地表吸应力的绝对值、环向应力系数、外黏聚力的增加而明显减小,而合力作用点高度的变化却不大;线性吸应力下的基坑侧向土压力大于均布吸应力下的,但均布吸应力下的侧向土压力变化更显著。 展开更多
关键词 圆形基坑 侧向土压力 空间土拱效应 吸应力 极限平衡法
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土力学的物理化学基础
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作者 韦昌富 《岩土工程学报》 北大核心 2026年第2期225-249,共25页
骨架(矿物)-水相互作用是影响土体工程力学性质的根本因素,但这一物理化学机制在经典土力学理论中长期未能被系统刻画,导致现有理论在解决多场耦合问题时存在明显局限,其中涉及黏土和化学问题尤为突出。为此,本文首次融合多孔介质连续... 骨架(矿物)-水相互作用是影响土体工程力学性质的根本因素,但这一物理化学机制在经典土力学理论中长期未能被系统刻画,导致现有理论在解决多场耦合问题时存在明显局限,其中涉及黏土和化学问题尤为突出。为此,本文首次融合多孔介质连续理论与经典物理化学原理,建立了能够统一表征骨架-水相互作用的理论框架,用于定量描述饱和与非饱和土的热-流-力-化学多过程耦合行为。通过定义骨架-水相互作用势,提出了孔隙水组分相对化学势的概念,并构建了相对化学势的一般表达式以及多相孔隙介质系统的平衡条件;通过引入广义有效应力原理,推导了广义有效应力公式;建立了多相多组分渗流控制方程,揭示了热渗透与化学渗透的作用机制,并建立了理论上自洽的多相流模型;确定了孔隙水-冰/水合物体系的相平衡条件,阐明了相变过程与土体抗剪强度之间的内在联系。本文不仅为多物理场耦合作用下多相多孔介质的力学行为与本构模拟提供了统一的物理化学与连续介质力学理论基础,也为拓展土力学理论体系、提升其工程预测能力提供了新途径。 展开更多
关键词 骨架-水相互作用 广义有效应力 渗流 渗透现象 相平衡
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时滞效应下双层耦合网络舆情传播动力学模型
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作者 徐会杰 马静珂 《计算机应用研究》 北大核心 2026年第3期811-817,共7页
针对社交媒体环境中舆情传播的动态过程,探讨了信息传播与消亡过程中存在的时间滞后对官方-民间双层耦合网络舆情演化的影响。首次建立官方层(OLN)与民间层(CLN)耦合的双层网络传播动力学框架,并引入时滞参数τ刻画权威信息发布与公众... 针对社交媒体环境中舆情传播的动态过程,探讨了信息传播与消亡过程中存在的时间滞后对官方-民间双层耦合网络舆情演化的影响。首次建立官方层(OLN)与民间层(CLN)耦合的双层网络传播动力学框架,并引入时滞参数τ刻画权威信息发布与公众响应的延迟过程,通过稳定性理论及Hopf分岔分析,研究系统平衡点的存在性与稳定性。时滞τ存在一个临界值τ_(c),当τ<τ_(c)时,系统渐近稳定,舆情逐渐消亡;当τ>τ_(c)时,系统失稳并发生Hopf分岔,舆情将呈现周期性波动。OLN的阻止率和推进率均能降低传播阈值R_(0),其中阻止率对控制舆情传播作用更为显著。时滞是影响双层网络舆情稳定性的关键因素,官方迅速捕捉舆情动态并及时干预能够降低舆情传播风险。 展开更多
关键词 时滞效应 网络舆情 双层网络 传播阈值 平衡点
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Equilibrium and kinetic Si isotope fractionation factors and their implications for Si isotope distributions in the Earth's surface environments 被引量:3
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作者 Hong-tao He Siting Zhang +1 位作者 Chen Zhu Yun Liu 《Acta Geochimica》 EI CAS CSCD 2016年第1期15-24,共10页
Several important equilibrium Si isotope fractionation factors among minerals,organic molecules and the H_4SiO_4 solution are complemented to facilitate the explanation of the distributions of Si isotopes in Earth'... Several important equilibrium Si isotope fractionation factors among minerals,organic molecules and the H_4SiO_4 solution are complemented to facilitate the explanation of the distributions of Si isotopes in Earth's surface environments.The results reveal that,in comparison to aqueous H_4SiO_4,heavy Si isotopes will be significantly enriched in secondary silicate minerals.On the contrary,quadra-coordinated organosilicon complexes are enriched in light silicon isotope relative to the solution.The extent of ^(28)Si-enrichment in hyper-coordinated organosilicon complexes was found to be the largest.In addition,the large kinetic isotope effect associated with the polymerization of monosilicic acid and dimer was calculated,and the results support the previous statement that highly ^(28)Sienrichment in the formation of amorphous quartz precursor contributes to the discrepancy between theoretical calculations and field observations.With the equilibrium Si isotope fractionation factors provided here,Si isotope distributions in many of Earth's surface systems can be explained.For example,the change of bulk soil δ^(30)Si can be predicted as a concave pattern with respect to the weathering degree,with the minimum value where allophane completely dissolves and the total amount of sesquioxides and poorly crystalline minerals reaches their maximum.When,under equilibrium conditions,the well-crystallized clays start to precipitate from the pore solutions,the bulk soil δ^(30)Si will increase again and reach a constant value.Similarly,the precipitation of crystalline smectite and the dissolution of poorly crystalline kaolinite may explain the δ^(30)Si variations in the ground water profile.The equilibrium Si isotope fractionations among the quadracoordinated organosilicon complexes and the H_4SiO_4solution may also shed light on the Si isotope distributions in the Si-accumulating plants. 展开更多
关键词 Si isotopes equilibrium fractionation factor Quantum chemistry calculation Cluster model Kinetic isotope effect
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Effects of Chemical Reactions in the Hypersonic Reacting Flow around Blunt Bodies
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作者 ZHAO Faming WANG Jiangfeng +1 位作者 FAN Xiaofeng YANG Tianpeng 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2019年第1期71-79,共9页
The effects of chemical reactions in the hypersonic reacting flow are investigated using an integrated algorithm considering simultaneously two different reaction mechanisms,i.e.,including the high temperature air non... The effects of chemical reactions in the hypersonic reacting flow are investigated using an integrated algorithm considering simultaneously two different reaction mechanisms,i.e.,including the high temperature air nonequilibrium chemical reactions and the H_2-air combustion reactions. The program is validated by the air non-equilibrium flow at Mach number of 25.9 with the RAM C-II configuration and the shock-induced combustion flow at Mach number of 4.512 6 around a sphere,respectively. Furthermore,the mixed reacting flow with the Mach number of 10.0 with an opposing jet of hydrogen is numerically analyzed. The results show that the program is reliable,and the effects of chemical reactions engender in the decrease of peak temperature along characteristic lines,as well as on the surface. The production of water is augmented in the region with high ratio of oxygen to hydrogen and weakened in the area with low ratio of oxygen to hydrogen by the air chemical non-equilibrium effects. 展开更多
关键词 HYPERSONIC air CHEMICAL NON-equilibrium combustion effectS of CHEMICAL reaction
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Binding Equilibrium Studies Between Co^(2+) and HSA or BSA 被引量:3
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作者 BIAN He dong LIANG Hong +2 位作者 TU Chu qiao ZHANG Hong zhi SHEN Pan wen 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2000年第3期276-279,共4页
关键词 Co 2+ serum albumin equilibrium dialysis Coordination analysis Positive cooperative effect
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