Axial liquid dispersion was experimentally studied in liquid-solid and gas-liquid-solid magnetically stabilized beds using the ferromagnetic catalyst of SRNA-4 as the solid phase. The effects of operating factors and ...Axial liquid dispersion was experimentally studied in liquid-solid and gas-liquid-solid magnetically stabilized beds using the ferromagnetic catalyst of SRNA-4 as the solid phase. The effects of operating factors and fluid characters, such as superficial liquid velocity, superficial gas velocity, magnetic field intensity, liquid viscosity and surface tension, on axial dispersion coefficients of liquid were investigated. The dispersion coefficients increased with the increase of superficial liquid velocity and superficial gas velocity, and decreased with the increase of liquid viscosity, liquid surface tension and magnetic field intensity. A correlation equation of Peclet number was obtained for both liquid-solid and gas-liquid-solid magnetically stabilized bed.展开更多
The nonlinear coupled-mode equations are rewritten by even and odd modes.We study modulation instability(MI) of dispersion-shifted fiber couplers when either even or odd mode is launched alone by using zero-dispersion...The nonlinear coupled-mode equations are rewritten by even and odd modes.We study modulation instability(MI) of dispersion-shifted fiber couplers when either even or odd mode is launched alone by using zero-dispersion wavelength relatively long(quasi-cw) pulses.The result shows that there are new types of MI in both the normal-dispersion and the anomalous-dispersion regimes.MI is concerned with forth-order dispersion and has no relation with third-order dispersion.Quasi-cw can be changed into pulses array under certain conditions.We can extract super short pulse from this.Furthermore,the bandwidth of gain spectra widens and its strength accretes as the input power increases.展开更多
Axial liquid dispersion was experimentally studied in liquid-solid and gas-liquid-solid magnetically sta- bilized beds using the ferromagnetic catalyst of SRNA-4 as the solid phase. The effects of operating factors an...Axial liquid dispersion was experimentally studied in liquid-solid and gas-liquid-solid magnetically sta- bilized beds using the ferromagnetic catalyst of SRNA-4 as the solid phase. The effects of operating factors and fluid characters, such as superficial liquid velocity, superficial gas velocity, magnetic field intensity, liquid viscosity and surface tension, on axial dispersion coefficients of liquid were investigated. The dispersion coefficients in- creased with the increase of superficial liquid velocity and superficial gas velocity, and decreased with the increase of liquid viscosity, liquid surface tension and magnetic field intensity. A correlation equation of Peclet number was obtained for both liquid-solid and gas-liquid-solid magnetically stabilized bed.展开更多
The extraction of rare earths by long-chain fatty acid in kerosene from sulphate system was described.It was demonstrated from the experimental results that the ratio of kerosene: fatty acid: isooctanol = 55 : 30: 15 ...The extraction of rare earths by long-chain fatty acid in kerosene from sulphate system was described.It was demonstrated from the experimental results that the ratio of kerosene: fatty acid: isooctanol = 55 : 30: 15 ( V/V),By the saturation capability method and the slope method, the extracted reaction mechanism of the extraction of rare earth was studied.It is shown that the extraction reaction conform to the cation exchange reaction mechanism.The extracted sequence of rare earth was determined in this system and it is shown that there is no tetrad effect and the position of yttrium is between lanthanum and cerium.展开更多
Liquids to be broken up using a prefilming airblast atomizer are usually Newton liquids with relatively low viscosities.While in some industrial processes,such as spray drying,liquids to be atomized are high concentra...Liquids to be broken up using a prefilming airblast atomizer are usually Newton liquids with relatively low viscosities.While in some industrial processes,such as spray drying,liquids to be atomized are high concentration suspensions or non-Newtonian fluids with high viscosities.In this paper,non-Newtonian fluids with viscosity up to 4.4 Pa·s were effectively atomized using a specially designed prefilming airblast atomizer.The atomizer enabled liquid to extend to a thickness-adjustable film and forced the atomizing air stream to swirl with 30° or 45° through gas distributors with spiral slots.The liquid film was impinged by the swirling air stream resulting in the disintegration of the film into drops.Drop sizes were measured using a laser diffraction technique.An improved four-parameter mathematical model was established to relate the Sauter mean diameter of drops to the atomization conditions in terms of power dependencies on three dimensionless groups:Weber number,Ohnesorge number and air liquid mass ratio.The friction on the surface of the liquid film made by swirling air stream played an important role in the prefilming atomization at the conditions of low air velocity and low liquid viscosity.In this case,the liquid film was disintegrated into drops according to the classical wavy-sheet mechanism,thus thinner liquid films and high swirl levels of the atomizing air produced smaller drops.With the increase of the air velocity and the liquid viscosity,the effect of the friction on the prefilming atomization relatively weakened,whereas the impingement on the liquid film made by atomizing air stream in a direction normal to the liquid film and corresponding momentum transfer gradually strengthened and eventually dominated the disruption of liquid into drops,which induced that the initial thickness of the liquid film and the swirl of atomizing air stream exercised a minor influence on the drop sizes.展开更多
The aim of this paper is to review the theory of equivalence as interpreted by some of the most innovative theorists in this field Jakobson,Nida and Taber,Catford,and Baker.
Just as students have different personalities, so do they have various learning styles. Why Otherwise might two people,compatible in age, intelligence and expectations, exposed to the same amount of opportunity, react...Just as students have different personalities, so do they have various learning styles. Why Otherwise might two people,compatible in age, intelligence and expectations, exposed to the same amount of opportunity, react so differently?Although an individual’s learning style is regarded as relatively fixed and not easily changed, it is possible to help learners explore their own preferences and to shape their learning approaches to meet the demands of the requirements of what they intend to achieve. Using Honey and Mumford’s Questionnaire and the systemized theory behind the questionnaire for analysis, this paper presents two arguments: 1. Trainers can help learners identify their learning style preferences and increase their awareness about them.2. Learners can become more effective learners once they are aware of their learning styles and the strong points and weak points of the different styles. The results of the investigation support the two arguments.展开更多
On the basis of a detailed introduction to the concept of language learners’needs, this paper illustrates the importance of needs analysis, both pre course analysis and ongoing analysis, in curriculum designing. By d...On the basis of a detailed introduction to the concept of language learners’needs, this paper illustrates the importance of needs analysis, both pre course analysis and ongoing analysis, in curriculum designing. By doing so, teachers can not only collect factual information for the purpose of setting broad goals related to language content; but also gather information about learners which can be used to guide the learning process once it’s under way. Learners, on the other hand, can be aware of their own learning under the direction of the specified objectives.展开更多
基金Supported by the National Natural Science Foundation of China (No.20206023) and SIN0PEC (No.X504029).
文摘Axial liquid dispersion was experimentally studied in liquid-solid and gas-liquid-solid magnetically stabilized beds using the ferromagnetic catalyst of SRNA-4 as the solid phase. The effects of operating factors and fluid characters, such as superficial liquid velocity, superficial gas velocity, magnetic field intensity, liquid viscosity and surface tension, on axial dispersion coefficients of liquid were investigated. The dispersion coefficients increased with the increase of superficial liquid velocity and superficial gas velocity, and decreased with the increase of liquid viscosity, liquid surface tension and magnetic field intensity. A correlation equation of Peclet number was obtained for both liquid-solid and gas-liquid-solid magnetically stabilized bed.
基金National Natural Science Foun-dation of China (No.60468001)
文摘The nonlinear coupled-mode equations are rewritten by even and odd modes.We study modulation instability(MI) of dispersion-shifted fiber couplers when either even or odd mode is launched alone by using zero-dispersion wavelength relatively long(quasi-cw) pulses.The result shows that there are new types of MI in both the normal-dispersion and the anomalous-dispersion regimes.MI is concerned with forth-order dispersion and has no relation with third-order dispersion.Quasi-cw can be changed into pulses array under certain conditions.We can extract super short pulse from this.Furthermore,the bandwidth of gain spectra widens and its strength accretes as the input power increases.
基金Supported by the National Natural Science Foundation of China (No.20206023) and SINOPEC (No.X504029).
文摘Axial liquid dispersion was experimentally studied in liquid-solid and gas-liquid-solid magnetically sta- bilized beds using the ferromagnetic catalyst of SRNA-4 as the solid phase. The effects of operating factors and fluid characters, such as superficial liquid velocity, superficial gas velocity, magnetic field intensity, liquid viscosity and surface tension, on axial dispersion coefficients of liquid were investigated. The dispersion coefficients in- creased with the increase of superficial liquid velocity and superficial gas velocity, and decreased with the increase of liquid viscosity, liquid surface tension and magnetic field intensity. A correlation equation of Peclet number was obtained for both liquid-solid and gas-liquid-solid magnetically stabilized bed.
文摘The extraction of rare earths by long-chain fatty acid in kerosene from sulphate system was described.It was demonstrated from the experimental results that the ratio of kerosene: fatty acid: isooctanol = 55 : 30: 15 ( V/V),By the saturation capability method and the slope method, the extracted reaction mechanism of the extraction of rare earth was studied.It is shown that the extraction reaction conform to the cation exchange reaction mechanism.The extracted sequence of rare earth was determined in this system and it is shown that there is no tetrad effect and the position of yttrium is between lanthanum and cerium.
文摘Liquids to be broken up using a prefilming airblast atomizer are usually Newton liquids with relatively low viscosities.While in some industrial processes,such as spray drying,liquids to be atomized are high concentration suspensions or non-Newtonian fluids with high viscosities.In this paper,non-Newtonian fluids with viscosity up to 4.4 Pa·s were effectively atomized using a specially designed prefilming airblast atomizer.The atomizer enabled liquid to extend to a thickness-adjustable film and forced the atomizing air stream to swirl with 30° or 45° through gas distributors with spiral slots.The liquid film was impinged by the swirling air stream resulting in the disintegration of the film into drops.Drop sizes were measured using a laser diffraction technique.An improved four-parameter mathematical model was established to relate the Sauter mean diameter of drops to the atomization conditions in terms of power dependencies on three dimensionless groups:Weber number,Ohnesorge number and air liquid mass ratio.The friction on the surface of the liquid film made by swirling air stream played an important role in the prefilming atomization at the conditions of low air velocity and low liquid viscosity.In this case,the liquid film was disintegrated into drops according to the classical wavy-sheet mechanism,thus thinner liquid films and high swirl levels of the atomizing air produced smaller drops.With the increase of the air velocity and the liquid viscosity,the effect of the friction on the prefilming atomization relatively weakened,whereas the impingement on the liquid film made by atomizing air stream in a direction normal to the liquid film and corresponding momentum transfer gradually strengthened and eventually dominated the disruption of liquid into drops,which induced that the initial thickness of the liquid film and the swirl of atomizing air stream exercised a minor influence on the drop sizes.
文摘The aim of this paper is to review the theory of equivalence as interpreted by some of the most innovative theorists in this field Jakobson,Nida and Taber,Catford,and Baker.
文摘Just as students have different personalities, so do they have various learning styles. Why Otherwise might two people,compatible in age, intelligence and expectations, exposed to the same amount of opportunity, react so differently?Although an individual’s learning style is regarded as relatively fixed and not easily changed, it is possible to help learners explore their own preferences and to shape their learning approaches to meet the demands of the requirements of what they intend to achieve. Using Honey and Mumford’s Questionnaire and the systemized theory behind the questionnaire for analysis, this paper presents two arguments: 1. Trainers can help learners identify their learning style preferences and increase their awareness about them.2. Learners can become more effective learners once they are aware of their learning styles and the strong points and weak points of the different styles. The results of the investigation support the two arguments.
文摘On the basis of a detailed introduction to the concept of language learners’needs, this paper illustrates the importance of needs analysis, both pre course analysis and ongoing analysis, in curriculum designing. By doing so, teachers can not only collect factual information for the purpose of setting broad goals related to language content; but also gather information about learners which can be used to guide the learning process once it’s under way. Learners, on the other hand, can be aware of their own learning under the direction of the specified objectives.