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加拿大大学的旅游相关专业学制教育体系现状研究 被引量:4
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作者 黄向 《旅游学刊》 CSSCI 北大核心 2005年第S1期47-51,共5页
本文通过Internet搜索等方法以加拿大排名前20名的大学为样本研究了加拿大大学的旅游相关专业学制教育体系的现状。分别从机构设置、本科生教育和研究生教育三个方面进行了描述,并总结了这三方面的特点。在讨论部分,本文以加拿大滑铁卢... 本文通过Internet搜索等方法以加拿大排名前20名的大学为样本研究了加拿大大学的旅游相关专业学制教育体系的现状。分别从机构设置、本科生教育和研究生教育三个方面进行了描述,并总结了这三方面的特点。在讨论部分,本文以加拿大滑铁卢大学为例说明了学生对旅游专业和教育的认同程度。 展开更多
关键词 加拿大 旅游 学制教育系统
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广东教育会对“壬戌学制”的贡献 被引量:2
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作者 熊贤君 《教育学报》 CSSCI 北大核心 2019年第1期99-106,共8页
中国近现代正式颁布了4个学制,虽然各有其地位,但1922年所颁布的"壬戌学制",被认为是最适应中国国情,实施时间最长,最符合儿童身心发展规律的学校系统制度。这个学制在起草和修订过程中,广东省教育会发挥了重要作用。其基本... 中国近现代正式颁布了4个学制,虽然各有其地位,但1922年所颁布的"壬戌学制",被认为是最适应中国国情,实施时间最长,最符合儿童身心发展规律的学校系统制度。这个学制在起草和修订过程中,广东省教育会发挥了重要作用。其基本精神、重要学段划分、学校和课程设置、学生个性发展等,基本采用了广东省教育会提交的学制系统改革案的思想与举措。对广东省教育会的贡献,学制系统改革议决案和"壬戌学制"公布后,教育界、学术界都给予了很高的评价。 展开更多
关键词 全国教育会联合会 广东教育会 学制系统改革 “壬戌学制
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Evolutionary analysis of green credit and automobile enterprises under the mechanism of dynamic reward and punishment based on government regulation
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作者 Yu Dong Xiaoyu Huang +1 位作者 Hongan Gan Xuyang Liu 《中国科学技术大学学报》 CAS CSCD 北大核心 2024年第5期49-62,I0007,共15页
To explore the green development of automobile enterprises and promote the achievement of the“dual carbon”target,based on the bounded rationality assumptions,this study constructed a tripartite evolutionary game mod... To explore the green development of automobile enterprises and promote the achievement of the“dual carbon”target,based on the bounded rationality assumptions,this study constructed a tripartite evolutionary game model of gov-ernment,commercial banks,and automobile enterprises;introduced a dynamic reward and punishment mechanism;and analyzed the development process of the three parties’strategic behavior under the static and dynamic reward and punish-ment mechanism.Vensim PLE was used for numerical simulation analysis.Our results indicate that the system could not reach a stable state under the static reward and punishment mechanism.A dynamic reward and punishment mechanism can effectively improve the system stability and better fit real situations.Under the dynamic reward and punishment mechan-ism,an increase in the initial probabilities of the three parties can promote the system stability,and the government can im-plement effective supervision by adjusting the upper limit of the reward and punishment intensity.Finally,the implementa-tion of green credit by commercial banks plays a significant role in promoting the green development of automobile enter-prises. 展开更多
关键词 automobile enterprises green credit system dynamics reward and punishment mechanism
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缓解培训与学历教育矛盾的设想与对策 被引量:1
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作者 王虹 《天津职业院校联合学报》 2010年第1期33-37,共5页
我国的教育资源布局不均衡,资源利用也不科学。要采用"蓝印毕业证书"制度,赋予培训以学历教育功能;要改革高考制度与运行模式,用5种人才培养模式实现教育公平。
关键词 教育资源布局 培训 学历教育 高考制度 运行模式 学制系统
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论高职教育与高等教育大众化的双向互动——基于国际比较的视角
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作者 侯小兵 张继华 《职业技术教育》 2007年第7期83-86,共4页
对中外高等教育大众化的比较分析显示,经济发展与高等教育大众化,高等教育大众化与高职教育发展之间存在深刻的互动关系。在有中国特色的高等教育大众化发展进程中,高职教育发展必须健全学制系统,完善法制体系,创新办学体制。
关键词 高等教育大众化 高职教育 经济发展 互动 学制系统 法制体系
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Vibration control of pedestrian-bridge vertical dynamic coupling interaction based on biodynamic model 被引量:2
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作者 朱前坤 李宏男 +1 位作者 南娜娜 杜永峰 《Journal of Southeast University(English Edition)》 EI CAS 2017年第2期209-215,共7页
The human-induced vertical vibration serviceability of low-frequency and lightweight footbridges is studied based on the moving mass-spring-damper(MMSD) biodynamic model, and the mass damper(TMD) with different op... The human-induced vertical vibration serviceability of low-frequency and lightweight footbridges is studied based on the moving mass-spring-damper(MMSD) biodynamic model, and the mass damper(TMD) with different optimal model parameters being used to control the vertical vibration.First, the MMSD biodynamic model is employed to simulate the pedestrians, and the time-varying control equations of the vertical dynamic coupling system of the pedestrian-bridgeTMD are established with the consideration of pedestrianbridge dynamic interaction; and the equations are solved by using the Runge-Kutta-Felhberg integral method with variable step size. Secondly, the footbridge dynamic response is calculated under the model of pedestrian-structure dynamic interaction and the model of moving load when the pedestrian pace frequency is consistent with the natural frequency of footbridge. Finally, a comparative study and analysis are made on the control effects of the vertical dynamic coupling system in different optimal models of the TMD. The calculation results show that the pedestrian-bridge dynamic interaction cannot be ignored when the vertical human-induced vibration serviceability of low-frequency and light-weight footbridge is evaluated. The TMD can effectively reduce the vibration under the resonance of pedestrian-bridge, and TMD parameters are recommended for the determination by the Warburton optimization model. 展开更多
关键词 FOOTBRIDGE vibration serviceability biodynamic dynamic coupling system vibration control
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关于实行职业教育制度的思考
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作者 吴福生 《教育与职业》 北大核心 1995年第5期4-5,共2页
关键词 职业教育制度 教育法 职业培训 学制系统
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Stability of Three-Dimensional Trunk Motion
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作者 郭巧 《Journal of Beijing Institute of Technology》 EI CAS 1998年第1期49-54,共6页
Aim To analyse stability of the three-dimensional rotational movements of a human torso system under perturbations using anatomical data of muscles (McGill, 1992). Methods To use the linearized analysis methods and a ... Aim To analyse stability of the three-dimensional rotational movements of a human torso system under perturbations using anatomical data of muscles (McGill, 1992). Methods To use the linearized analysis methods and a special model in which the effect of ligamentous and passive resitance by discs and fibers is included. Results The model is capable of predicting the muscle forces,and joint reaction forces at the L5/Sl which are the biomechani- cal factors used to asses the risk of the discs and annulus fibers. Conclusions It can also be used to analyze and neural excitation levels for a diverse Set of trunk movement. 展开更多
关键词 BIOCONTROL BIOMECHANICS system stability analysis
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Iterative Learning Control With Incomplete Information: A Survey 被引量:13
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作者 Dong Shen Senior Member IEEE 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2018年第5期885-901,共17页
Abstract--This paper conducts a survey on iterative learn- ing control (ILC) with incomplete information and associated control system design, which is a frontier of the ILC field. The incomplete information, includ... Abstract--This paper conducts a survey on iterative learn- ing control (ILC) with incomplete information and associated control system design, which is a frontier of the ILC field. The incomplete information, including passive and active types, can cause data loss or fragment due to various factors. Passive incomplete information refers to incomplete data and information caused by practical system limitations during data collection, storage, transmission, and processing, such as data dropouts, delays, disordering, and limited transmission bandwidth. Active incomplete information refers to incomplete data and information caused by man-made reduction of data quantity and quality on the premise that the given objective is satisfied, such as sampling and quantization. This survey emphasizes two aspects: the first one is how to guarantee good learning performance and tracking performance with passive incomplete data, and the second is how to balance the control performance index and data demand by active means. The promising research directions along this topic are also addressed, where data robustness is highly emphasized. This survey is expected to improve understanding of the restrictive relationship and trade-off between incomplete data and tracking performance, quantitatively, and promote further developments of ILC theory. Index Terms--Data dropout, data robustness, incomplete in- formation, iterative learning controi(ILC), quantized control, sampled control, varying lengths. 展开更多
关键词 Data dropout data robustness incomplete information iterative learning control(ILC) quantized control sampled control varying lengths
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Improved Smith prediction monitoring AGC system based on feedback-assisted iterative learning control 被引量:4
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作者 张浩宇 孙杰 +2 位作者 张殿华 陈树宗 张欣 《Journal of Central South University》 SCIE EI CAS 2014年第9期3492-3497,共6页
The performance of Smith prediction monitoring automatic gauge control(AGC) system is influenced by model mismatching greatly in strip rolling process. Aiming at this problem, a feedback-assisted iterative learning co... The performance of Smith prediction monitoring automatic gauge control(AGC) system is influenced by model mismatching greatly in strip rolling process. Aiming at this problem, a feedback-assisted iterative learning control strategy, which learned unknown modeling error by using previous control information repeatedly, was introduced into Smith prediction monitoring AGC system. Firstly, conventional Smith predictor and improved Smith predictor with PI-P controller were analyzed. Secondly, on the basis of establishing of feedback-assisted iterative learning control strategy for improved Smith predictor, process control signal update law and control error were deduced, then convergence condition of this strategy was put forward and proved. Finally, after modeling the automatic position control system, the PI-P Smith prediction monitoring AGC system with feedback-assisted iterative learning control was researched through simulation. Simulation results indicate that this system remains stable during model mismatching. The robustness and response of monitoring AGC is improved by development of feedback-assisted iterative learning control strategy for PI-P Smith predictor. 展开更多
关键词 automatic gauge control Smith predictor monitoring automatic gauge control (AGC) feedback-assisted iterativelearning control automatic position control
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Dynamic Thermal Model and Temperature Control of Proton Exchange Membrane Fuel Cell Stack 被引量:5
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作者 邵庆龙 卫东 +1 位作者 曹广益 朱新坚 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2005年第2期218-224,共7页
A dynamic thermal transfer model of a proton exchange membrane fuel cell (PEMFC) stack is developed based on energy conservation in order to reach better temperature control of PEMFC stack. Considering its uncertain p... A dynamic thermal transfer model of a proton exchange membrane fuel cell (PEMFC) stack is developed based on energy conservation in order to reach better temperature control of PEMFC stack. Considering its uncertain parameters and disturbance, we propose a robust adaptive controller based on backstepping algorithm of Lyaponov function. Numerical simulations indicate the validity of the proposed controller. 展开更多
关键词 proton exchange membrane fuel cell stack dynamic thermal transfer model temperature control
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Error Analysis of Three Degree-of-Freedom Changeable Parallel Measuring Mechanism 被引量:7
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作者 CHENG Gang GE Shi-rong WANG Yong 《Journal of China University of Mining and Technology》 EI 2007年第1期101-104,共4页
A three degree-of-freedom (DOF) planar changeable parallel mechanism is designed by means of control of different drive parameters. This mechanism possesses the characteristics of two kinds of parallel mechanism. Base... A three degree-of-freedom (DOF) planar changeable parallel mechanism is designed by means of control of different drive parameters. This mechanism possesses the characteristics of two kinds of parallel mechanism. Based on its topologic structure, a coordinate system for position analysis is set-up and the forward kinematic solutions are analyzed. It was found that the parallel mechanism is partially decoupled. The relationship between original errors and position-stance error of moving platform is built according to the complete differential-coefficient theory. Then we present a special example with theory values and errors to evaluate the error model, and numerical error solutions are gained. The investigations concentrating on mechanism errors and actuator errors show that the mechanism errors have more influences on the position-stance of the moving platform. It is demonstrated that improving manufacturing and assembly techniques can greatly reduce the moving platform error. The small change in position-stance error in different kinematic positions proves that the error-compensation of software can improve considerably the precision of parallel mechanism. 展开更多
关键词 parallel mechanism changeable measuring mechanism kinematics forward analysis error model error analysis
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Automobile active suspension system with fuzzy control 被引量:3
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作者 刘少军 黄中华 陈毅章 《Journal of Central South University of Technology》 EI 2004年第2期206-209,共4页
A quarter-automobile active suspension model was proposed. High speed on/off solenoid valves were used as control valves and fuzzy control was chosen as control method . Based on force analyses of system parts, a math... A quarter-automobile active suspension model was proposed. High speed on/off solenoid valves were used as control valves and fuzzy control was chosen as control method . Based on force analyses of system parts, a mathematical model of the active suspension system was established and simplified by linearization method. Simulation study was conducted with Matlab and three scale coefficients of fuzzy controller (ke, kec, ku) were acquired. And an experimental device was designed and produced. The results indicate that the active suspension system can achieve better vibration isolation performance than passive suspension system, the displacement amplitude of automobile body can be reduced to 55%. Fuzzy control is an effective control method for active suspension system. 展开更多
关键词 active suspension system fuzzy control high speed on/off solenoid valve SIMULATION
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Aluminum matrix composites reinforced by in situ Al_2O_3 and Al_3Zr particles fabricated via magnetochemistry reaction 被引量:3
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作者 赵玉涛 张松利 陈刚 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第11期2129-2133,共5页
Aluminum matrix composites reinforced by in situ Al2O3 and Al3Zr particles are fabricated from A356-Zr(CO3)2 system via magnetochemistry reaction,and the morphologies,sizes and distributions of the in situ particles a... Aluminum matrix composites reinforced by in situ Al2O3 and Al3Zr particles are fabricated from A356-Zr(CO3)2 system via magnetochemistry reaction,and the morphologies,sizes and distributions of the in situ particles as well as the microstructures,mechanical mechanisms of the composites are investigated by XRD,SEM,TEM and in situ tensile tests.The results indicate that with the pulsed magnetic field assistance,the morphologies of the in situ particles are mainly with ball-shape,the sizes are in nanometer scale and the distributions in the matrix are uniform.The interfaces between the in situ particles and the aluminum matrix are net and no interfacial outgrowth is observed.These are due to the strong vibration induced by the applied magnetic field in the aluminum melt,which in turn,accelerates the melt reactions.The effects of the magnetic field on the above contributions are discussed in detail. 展开更多
关键词 aluminum matrix composites magnetochemistry reaction Al2O3 AL3ZR in situ tensile
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Control of chemical chaos 被引量:2
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作者 李卫东 钱积新 《Journal of Coal Science & Engineering(China)》 2002年第2期84-87,共4页
Lyapunov exponents can act as the judgment rule whether the systems is chaotic or not.We propose an approach to control chaotic systems by varying the Lyapunov exponents of the system. At last we use this method to co... Lyapunov exponents can act as the judgment rule whether the systems is chaotic or not.We propose an approach to control chaotic systems by varying the Lyapunov exponents of the system. At last we use this method to control a chemical system. Both the theoretical analysis and the simulation results prove that this method can quickly and effectively stabilize the chaotic systems to the desire points. 展开更多
关键词 chaotic system Lyapunov exponents Jacobi matrix
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Multi-objective Fuzzy Optimization Algorithm for Separation-Recycle System 被引量:6
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作者 孙力 樊希山 姚平经 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2004年第2期221-226,共6页
Separation-recycle system is an important part in chemical process, and its optimization is a multiobjective problem. In this paper the process optimization procedure is proposed. The fuzzy optimization algorithm with... Separation-recycle system is an important part in chemical process, and its optimization is a multiobjective problem. In this paper the process optimization procedure is proposed. The fuzzy optimization algorithm with the concept of relative importance degree (RID) is utilized to transfer multi-objective optimization (MO-O) model into a single-objective optimization (SO-O) framework. The treatment of process condensate in synthesisa mmonia plant is taken as example to illustrate the optimization procedure, and the satisfactory result demonstrates feasibility and effectiveness of the suggested method. 展开更多
关键词 MULTI-OBJECTIVE fuzzy optimization relative importance degree
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Mathematical model of electric hydraulic and powered support control system at a plough mining face 被引量:2
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作者 ZHANG Wei HAN Xiao SUN Jing-jing 《Journal of China University of Mining and Technology》 EI 2008年第1期55-58,共4页
Given the actual working of a fully mechanized plough at a mining face, we have proposed a formula for running constraints between powered supports and a coal plough under assumed geological conditions of the coal fac... Given the actual working of a fully mechanized plough at a mining face, we have proposed a formula for running constraints between powered supports and a coal plough under assumed geological conditions of the coal face and, on this basis, established an automatic control model of powered supports for the coal plough face. We introduced the working principle of the powered support control system of the plough at the mining face. We established three advanced characteristics of this control system: response speed, reliability and easy maintenance of the system. As well, we briefly introduced, the principal function of primary and subordinate controllers and the realization of the communication system by a Single Bus. Ten controllers were constructed and tested in our laboratorium. The results show that the control model is practical and meets actual conditions. It provides a theoretical basis for designing a comouter control system for a oowered support system of a plough at a mining face. 展开更多
关键词 plough mining face powered supports CONSTRAINTS automatic control model
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A New Optimal Control System Design for Chemical Processes 被引量:1
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作者 丛二丁 胡明慧 +1 位作者 涂善东 邵惠鹤 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第12期1341-1346,共6页
Based on frequency response and convex optimization,a novel optimal control system was developed for chemical processes.The feedforward control is designed to improve the tracking performance of closed loop chemical s... Based on frequency response and convex optimization,a novel optimal control system was developed for chemical processes.The feedforward control is designed to improve the tracking performance of closed loop chemical systems.The parametric model is not required because the system directly utilizes the frequency response of the loop transfer function,which can be measured accurately.In particular,the extremal values of magnitude and phase can be solved according to constrained quadratic programming optimizer and convex optimization.Simulation examples show the effectiveness of the method.The design method is simple and easily adopted in chemical industry. 展开更多
关键词 control system frequency response convex optimization chemical processes
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Scheduling Multiple Orders per Job with Multiple Constraints on Identical Parallel Machines 被引量:1
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作者 王腾 周炳海 《Journal of Donghua University(English Edition)》 EI CAS 2013年第6期466-471,共6页
With a comprehensive consideration of multiple product types, past-sequence-dependent ( p-s-d ) setup times, and deterioration effects constraints in processes of wafer fabrication systems, a novel scheduling model ... With a comprehensive consideration of multiple product types, past-sequence-dependent ( p-s-d ) setup times, and deterioration effects constraints in processes of wafer fabrication systems, a novel scheduling model of multiple orders per job(MOJ) on identical parallel machines was developed and an immune genetic algorithm(IGA) was applied to solving the scheduling problem. A scheduling problem domain was described. A non-linear mathematical programming model was also set up with an objective function of minimizing total weighted earliness-tardlness penalties of the system. On the basis of the mathematical model, IGA was put forward. Based on the genetic algorithm (GA), the proposed algorithm (IGA) can generate feasible solutions and ensure the diversity of antibodies. In the process of immunization programming, to guarantee the algorithm's convergence performance, the modified rule of apparent tardiness cost with setups (ATCS) was presented. Finally, simulation experiments were designed, and the results indicated that the algorithm had good adaptability when the values of the constraints' characteristic parameters were changed and it verified the validity of the algorithm. 展开更多
关键词 multiple product types past-sequence-dependent p-s-d setup times deterioration effects identical parallel machines scheduline immune Penetic algorithm IGA
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Diffusion-controlled Adsorption Kinetics at Air/Solution Surface Studied by Maximum Bubble Pressure Method 被引量:1
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作者 刘俊吉 王创业 MESSOW Ulf 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2004年第4期577-581,共5页
In studying the diffusion-controlled adsorption kinetics of aqueous surfactant solutions at the air/solution surface by means of the maximal bubble pressure method, Fick's diffusion equation for a sphere should be... In studying the diffusion-controlled adsorption kinetics of aqueous surfactant solutions at the air/solution surface by means of the maximal bubble pressure method, Fick's diffusion equation for a sphere should be used. In this paper the equation was solved by means of Laplace transformation under different initial and boundary conditions. The dynamic surface adsorption F(t) for a surfactant solution, which was used to describe the diffusion-controlled adsorption kinetics at the solution surface, was derived. Different from the planar surface adsorption, the dynamic surface adsorption F(t) for the short time consists of two terms: one is the same as Ward-Tordai equation and the other reflects the geometric effect caused by the spherical bubble surface. This effect should not be neglected for the very small radius of the capillary. The equilibrium surface tension γeq and the dynamic surface tension γ(t) of aqueous C10E6 [CH3(CH2)9(OCH2CH2)6OH] solution at temperature 25℃ were measuredby means of Wilhelmy plate method and maximal bubble pressure method respectively. As t→ 0, the theoreticalanalysis is in good agreement with experimental results and the dependence of γ(t) on is linear. 展开更多
关键词 diffusion-controlled adsorption kinetics dynamic surface tension maximum bubble pressure method
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