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A Simple and Effective Test Method of the Emulsion stability

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Chinese Journal of Chemical Engineering 2001年第2期9卷 200-203页

作者：李啸风陈志荣李浩然韩世钧 DepartmentofChemistry，Hangzhou310027 China DepartmentofChemicalEngineering ZhejiangUniversityHangzhou310027China

An innovational test method was developed on the basis of redefinition of the emulsion stability. The stability was characterized by relative volume percentage of disperse phase demulsified thoroughly from the top part and the bottom part of an emulsion sample, each weighting the same amount, after being settled for a given time at constant temperature. Three series of emulsions were prepared and tested successfully, which were emulsions of paraffin oil and water stabilized with polyoxyethylene lauryl ether series (AEO3 and AEO9) at various HLBs, and emulsions of rapeseed oil and water stablized with sorbitan monoleate (Span80) and each of polyoxyethylene (20) sorbitan carboxylic esters (Tween20, Tween40, Tween60, Tween80 and Tween85) at different HLBs. It provedthat this method is especially workable while the boundaries are opaque in a wide range of HLBs and is capable of offering an accurate optimum HLB.

关键词： emulsion stability stability number optimum HLB

An Advanced Probabilistic Neural Network for the Design of Breakwater Armor Blocks

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China Ocean Engineering 2007年第4期21卷 597-610页

作者： Dookie KIM Dong Hyawn KIM Seongkyu CHANG Gil Lim YOON Department of Civil and Environmental Engineering Kunsan National UniversityKunsanJeonbukKorea Department of Ocean System Engineering Kunsan National UniversityKunsanJeonbukKorea Coastal Engineering Research Department KORDIAnsanGyeonggiKorea

In this study, an advanced probabilistic neural network （APNN） method is proposed to reflect the global probability density function （PDF） by summing up the heterogeneous local PDF which is automatically determined in the individual standard deviation of variables. The APNN is applied to predict the stability number of armor blocks of breakwaters using the experimental data of＇ van der Meet, and the estimated results of the APNN are compared with those of an empirical formula and a previous artificial neural network （ANN） model. The APNN shows better results in predicting the stability number of armor bilks of breakwater and it provided the promising probabilistic viewpoints by using the individual standard deviation in a variable.

关键词： breakwater armor block stability number multivariate gaussian distribution classigication artificial neural network (ANN) advanced probabilistic neural network (APNN)

Impact of spatially varying rock disturbance on rock slope stability

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第10期16卷 3907-3923页

作者： Dowon Park Radoslaw L.Michalowski Department of Civil Engineering College of EngineeringUniversity of SeoulSeoul02504South Korea Department of Civil and Environmental Engineering College of EngineeringUniversity of MichiganAnn ArborMI48109USA

Degradation of rock mass produced by rock blasting,stress relief,and other causes is an important factor in the assessment of rock *** as a disturbance factor,such degradation varies depending on blasting control,stress state and stress relief,and rock mass *** study focuses on the impact of disturbance on the safety of *** disturbance in the rock mass is characterized by the geometry of the disturbed zone,its size,the magnitude,and the decaying rate with the distance away from the slope surface.A method accounting for decay of rock disturbance is presented.A study of the impact of rock disturbance characteristics on the quantitative stability measures of slopes was carried *** characteristics included disturbed zone geometry,its thickness,the maximum magnitude of the disturbance factor,and the rate of disturbance *** thickness of the disturbed zone and the maximum factor of disturbance were found to have the greatest *** example,the factor of safety for a 45slope in low-quality rock mass can decrease from 1.96 to 1.09 as the thickness of the disturbed zone increases from 1/4 of slope height H to the double of H and the maximum disturbance factor increases from 0.5 to *** thickness of a disturbed zone was found to yield more conservative outcomes than the triangular zones *** critical failure surfaces were found to be shallow for high rates of disturbance decay,and they were the deepest for spatially uniform disturbance factors.

关键词： Disturbance decaying Blast damage Limit analysis Damage zone stability number

Comparison of seismic stability for slopes with tensile strength cut-off and cracks

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Journal of Mountain Science 2021年第12期18卷 3336-3347页

作者： ZHANG Ying-bin LIU Yan YUAN Ran HE Yi Department of Geotechnical Engineering Southwest Jiaotong UniversityChengdu 610031China Key Laboratory of High-speed Railway Engineering Ministry of Education Southwest Jiaotong UniversityChengdu 610031China Faculty of Geosciences and Environmental Engineering Southwest Jiaotong UniversityChengdu 611756China Department of Civil and Structural Engineering Kyushu UniversityFukuoka 819-0395Japan

The strength of geomaterials is typically predicted by the Mohr-Coulomb yield criterion in slope stability *** tensile strength of soils in this yield criterion,which is an extrapolation of the triaxial compression test results,is usually ***,the influences of tensile stresses in slopes are evaluated by two approaches:1)introducing cracks to eliminate the tensile stresses in slopes,and 2)truncating the strength envelope to reduce the tensile strength of the ***,comparative analyses of the two approaches have not been fully implemented,especially under dynamic *** this study,three slope failure mechanisms corresponding to the predictions of slope stability by the mentioned two approaches subjected to seismic loadings are systematically *** stability factor considering the pre-existing crack,crack formation,and tension cut-off are compared one *** most unfavorable crack locations corresponding to the different mechanisms are *** influence of tensile strength on the factor of safety of slopes is estimated as ***,the critical acceleration and the permanent displacement of slopes with pre-existing crack,and tension cut-off are derived in the framework of the kinematic theorem of limit *** vertical effects of seismic coefficient on critical acceleration and permanent displacement are *** can be drawn that the consideration of tension zone effects can sharply reduce the stability factor of slopes,especially for steep slopes and large horizontal seismic loads;different from the static condition,the slope with pre-existing crack is not always the most vulnerable to collapse,the tension cut-off mechanism in steep slopes may predict the lowest stability *** addition,the calculation shows that an evidently increase in the slope displacement is induced by the increasing downward vertical loads,while a decrease occurs if the vertical loads are upward.

关键词： Slope stability Tension zone Limit analysis Seismic loads stability number Permanent displacement