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From De Sitter Special Relativity and Snyder's Model to Complete Yang Model
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作者 于玥 吴宏途 郭汉英 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第11期819-824,共6页
The de Sitter special relativity on the Beltrami-de Sitter-spacetime and Snyder's model in the momentum space can be combined together with an IR-UV duality to get the complete Yang model at both classical and quantu... The de Sitter special relativity on the Beltrami-de Sitter-spacetime and Snyder's model in the momentum space can be combined together with an IR-UV duality to get the complete Yang model at both classical and quantum levels, which are related by the proposed Killing quantization. It is actually a special relativity based on the principle of relativity of three universal constants (c, ρp, R). 展开更多
关键词 principle of relativity de Sitter special relativity Snyder's model complete Yang model
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Nonlinear Electrical Impedance Tomography Method Using a Complete Electrode Model for the Characterization of Heterogeneous Domains
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作者 Jeongwoo Park Bong-Gu Jung Jun Won Kang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第3期1707-1735,共29页
This paper presents an electrical impedance tomography(EIT)method using a partial-differential-equationconstrained optimization approach.The forward problem in the inversion framework is described by a complete electr... This paper presents an electrical impedance tomography(EIT)method using a partial-differential-equationconstrained optimization approach.The forward problem in the inversion framework is described by a complete electrodemodel(CEM),which seeks the electric potential within the domain and at surface electrodes considering the contact impedance between them.The finite element solution of the electric potential has been validated using a commercial code.The inverse medium problem for reconstructing the unknown electrical conductivity profile is formulated as an optimization problem constrained by the CEM.The method seeks the optimal solution of the domain’s electrical conductivity to minimize a Lagrangian functional consisting of a least-squares objective functional and a regularization term.Enforcing the stationarity of the Lagrangian leads to state,adjoint,and control problems,which constitute the Karush-Kuhn-Tucker(KKT)first-order optimality conditions.Subsequently,the electrical conductivity profile of the domain is iteratively updated by solving the KKT conditions in the reduced space of the control variable.Numerical results show that the relative error of the measured and calculated electric potentials after the inversion is less than 1%,demonstrating the successful reconstruction of heterogeneous electrical conductivity profiles using the proposed EIT method.This method thus represents an application framework for nondestructive evaluation of structures and geotechnical site characterization. 展开更多
关键词 Electrical impedance tomography complete electrode model inverse medium problem Karush-Kuhn-Tucker(KKT)optimality conditions nondestructive evaluation of structures
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Complete convergence for arrays of rowwise negatively superadditive-dependent random variables and its applications 被引量:5
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作者 WU Yi WANG Xue-jun HU Shu-he 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2016年第4期439-457,共19页
In this paper, an exponential inequality for the maximal partial sums of negatively superadditive-dependent (NSD, in short) random variables is established. By uSing the exponen- tial inequality, we present some gen... In this paper, an exponential inequality for the maximal partial sums of negatively superadditive-dependent (NSD, in short) random variables is established. By uSing the exponen- tial inequality, we present some general results on the complete convergence for arrays of rowwise NSD random variables, which improve or generalize the corresponding ones of Wang et al. [28] and Chen et al. [2]. In addition, some sufficient conditions to prove the complete convergence are provided. As an application of the complete convergence that we established, we further investigate the complete consistency and convergence rate of the estimator in a nonparametric regression model based on NSD errors. 展开更多
关键词 exponential inequality complete convergence negatively superadditive-dependent random vari-ables nonparametric regression model complete consistency.
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Analysis of complete plasticity assumption for solid circular shaft under pure torsion and calculation of shear stress 被引量:1
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作者 刘光连 黄明辉 +2 位作者 谭青 李显方 刘振 《Journal of Central South University》 SCIE EI CAS 2011年第4期1018-1023,共6页
The distribution of shear stress on the cross-section of plastic metal solid circular shaft under pure torsion yielding, the applicability of complete plastic model assumption and the shear stress formula were researc... The distribution of shear stress on the cross-section of plastic metal solid circular shaft under pure torsion yielding, the applicability of complete plastic model assumption and the shear stress formula were researched. Based on the shear stress formula of circular shaft under pure torsion in elastic stage, the formula of torque in elastic stage and the definition of yield, it is obtained that the yielding stage of plastic metal shaft under pure torsion is only a surface phenomenon of torque-torsion angle relationship, and the distribution of shear stress is essentially different from that of tensile stress when yielding under uniaxial tension. The pure torsion platform-torsion angle and the shape of torque-torsion angle curve cannot change the distribution of shear stress on the shaft cross-section. The distribution of shear stress is still linear with the maximum shear stress ts. The complete plasticity model assumption is not in accordance with the actual situation of shaft under torsion. The experimental strength data of nine plastic metals are consistent with the calculated results of the new limiting strain energy strength theory (LSEST). The traditional yield stress formula for plastic shaft under torsion is reasonable. The shear stress formula based on the plane assumption in material mechanics is applicable for all loaded stages of torsion shaft. 展开更多
关键词 pure torsion YIELD complete plastic model assumption shear stress calculation limiting strain energy strength theory
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Combining SAD/SIR iteration and MR iteration in partial-model extension of proteins
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作者 张涛 武丽杰 +2 位作者 古元新 郑朝德 范海福 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第9期7-11,共5页
There are two kinds of dual-space partial-model extensions which involve the direct-method program OASIS. The first kind, named SAD/SIR iteration, uses SAD/SIR information, while the second kind, named molecular repla... There are two kinds of dual-space partial-model extensions which involve the direct-method program OASIS. The first kind, named SAD/SIR iteration, uses SAD/SIR information, while the second kind, named molecular replacement (MR) iteration, does not use that information. In general, the SAD/SIR iteration is more powerful since more experimental information is used. However, in most cases when protein structures are solved with the molecular replacement method, SAD/SIR information is not available. Thus the MR iteration is particularly useful for the completion of models from molecular replacement. The SAD/SIR iteration will be automatically used in OASIS for data sets containing SAD/SIR signals, while the MR iteration will be dedicated to data sets without SAD/SIR signals. The present paper shows that for data containing SAD/SIR signals, a combination of SAD/SIR iteration and MR iteration could lead to significantly better results than that obtained from the SAD/SIR iteration alone. 展开更多
关键词 OASIS dual-space phasing model completion proteins
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Dependence of Magnetic Properties of Rapidly Quenching (Nd,Pr)_x (FeCoZr)_(94-x)B_6 Bonded Magnets on Rare Earths Content 被引量:1
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作者 查五生 刘颖 +2 位作者 高升吉 连利仙 涂铭旌 《Journal of Rare Earths》 SCIE EI CAS CSCD 2004年第3期418-421,共4页
By using sub-overquenching and annealing method which has a wide processing window, (Nd, Pr), ( Fe-CoZr)(94-x)B-6(x = 12, 10.5, 10, 9) bonded magnets were prepared and the effect of rare earths content on magnetic pro... By using sub-overquenching and annealing method which has a wide processing window, (Nd, Pr), ( Fe-CoZr)(94-x)B-6(x = 12, 10.5, 10, 9) bonded magnets were prepared and the effect of rare earths content on magnetic properties was investigated. Being spun at sub-ove.quenching speed the as-spun ribbons consist of amorphous phases mixed with fine crystallites. After crystallization under optimum annealing conditions and bonded with 3.25% (mass fraction) epoxy, the magnets obtained the optimum magnetic properties. The rare earths content directly determines the magnetic properties. With the reduction of rare earths content, B-r increases but H-ci and (BH)(max) decrease. x = 10 is the critical value for the magnetic proper-ties change. Below this value, Br increases slowly meanwhile H-ci and (BH)(max) decrease strongly because alloy contains extra fractions of soft magnetic phase which are not coupled with the hard magnetic phase.. This experimental result is consistent with the calculated results using the model of volume fraction of soft magnetic phase coupled completely suggested. 展开更多
关键词 metal materials Pr-based permanent magnets nanocrystalline composite magnetic properties completely coupling model rare earths
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Complete canine spinal cord transection model: a large animal model for the translational research of spinal cord regeneration 被引量:9
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作者 Sufang Han Xing Li +1 位作者 Zhifeng Xiao Jianwu Dai 《Science China(Life Sciences)》 SCIE CAS CSCD 2018年第1期115-117,共3页
Traumatic spinal cord injury (SCI) usually results in devastating neurologic deficits and disability. In the United States,approximately 12,500 new cases are reported each year, while an estimated 100,000–140,000 new... Traumatic spinal cord injury (SCI) usually results in devastating neurologic deficits and disability. In the United States,approximately 12,500 new cases are reported each year, while an estimated 100,000–140,000 new cases occur every year in China (National Spinal Cord Injury Statistical Center, 2016).Spinal cord injuries are highly disabling and primarily affect young adults, and therefore create great psychological and financial burden on the affected individuals and their families. 展开更多
关键词 In complete canine spinal cord transection model SCI
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Size effect on longitudinal MOE of microtomed wood sections and relevant theoretical explanation 被引量:2
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作者 YU Yan JIANG Ze-hui TIAN Gen-lin 《Forestry Studies in China》 CAS 2009年第4期243-248,共6页
It has been repeatedly observed that the mechanical properties of microtomed wood sections are significantly lower than those of samples of normal size, but few investigations have been conducted to deal with this top... It has been repeatedly observed that the mechanical properties of microtomed wood sections are significantly lower than those of samples of normal size, but few investigations have been conducted to deal with this topic, especially based on theoretical approaches. We measured the longitudinal MOE of Chinese fir on microtomed sections ranging in thickness from 70 to 200 μm and compared these with the values of samples of normal size. The results indicate that the MOE of microtomed wood sections increases with thickness from 70 to 200 μm, but is significantly less than that of normal samples. A size effect coefficient of 2.63 is inferred based on statistical data for samples of normal size and 200 μm thick microtomed sections. Finally, an explanation based on a complete shear restraint model of cell walls and a single fiber multi-ply model is proposed for the size effect on stiffness of microtomed wood sections. 展开更多
关键词 a complete shear restraint model microtomed wood sections a single fiber multi-ply model size effect
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THE MOVEMENT AND THERMAL HISTORY OF AN ALUMINIUM PARTICLE IN A RF PLASMA GENERATOR
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作者 李明 陈允明 阎嘉坪 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 1993年第4期363-370,共8页
In previous studies on plasma-particle interaction, as far as we know, the rf plasma flow and temperature fields are all simulated by the non-self-consistent one-dimensional electromagnetic (1-D EM) field model. In th... In previous studies on plasma-particle interaction, as far as we know, the rf plasma flow and temperature fields are all simulated by the non-self-consistent one-dimensional electromagnetic (1-D EM) field model. In the present paper, the complete self-consistent two-dimensional electromagnetic (2-D EM) field model in- corporating the axial Lorentz force component, which is neglected in the 1-D model, is firstly adopted to calculate the aluminium particle trajectory and thermal history in atmospheric rf Ar plasma with the particle evaporation effect included. The cru- cial effect of reverse flow within the coil region on the particle trajectory is discovered and the results show that the 2-D EM field model must be adopted instead of the 1-D model when the plasma-particle interaction is studied. The effect of carrier gas flux on the particle movement and heating are also studied, resulting in some useful conclusions for both plasma theory and application. 展开更多
关键词 plasma-particle interaction rf plasma particle trajectory and thermal history complete 2-D rf plasma model.
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Clinical Data-Driven Finite Element Analysis of the Kinetics of Chewing Cycles in Order to Optimize Occlusal Reconstructions Dedicated to Professor Karl Stark Pister for his 95th birthday
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作者 Simon Martinez Jurgen Lenz +6 位作者 Hans Schindler Willi Wendler Stefan Rues Karl Schweizerhof Sophia Terebesi Nikolaos Nikitas Giannakopoulos Marc Schmitter 《Computer Modeling in Engineering & Sciences》 SCIE EI 2021年第12期1259-1281,共23页
The occlusal design plays a decisive role in the fabrication of dental restorations.Dentists and dental technicians depend on mechanical simulations of mandibular movement that are as accurate as possible,in particula... The occlusal design plays a decisive role in the fabrication of dental restorations.Dentists and dental technicians depend on mechanical simulations of mandibular movement that are as accurate as possible,in particular,to produce interference-free yet chewing-efficient dental restorations.For this,kinetic data must be available,i.e.,movements and deformations under the influence of forces and stresses.In the present study,so-called functional data were collected from healthy volunteers to provide consistent information for proper kinetics.For the latter purpose,biting and chewing forces,electrical muscle activity and jaw movements were registered synchronously,and individual magnetic resonance tomograms(MRI)were prepared.The acquired data were then added to a large complex finite element model of the complete masticatory system using the functional information obtained and individual anatomical geometries so that the kinetics of the chewing process and teeth grinding could be realistically simulated.This allows developing algorithms that optimize computer-aided manufacturing of dental prostheses close to occlusion.In this way,a failure-free function of the dental prosthesis can be guaranteed and its damage during usage can be reduced or prevented even including endosseous implants. 展开更多
关键词 Occlusal design mechanical simulations of mandibular movement finite element model of the complete masticatory system simulation of chewing process and teeth grinding
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Determining the Real Data Completeness of a Relational Dataset
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作者 Yong-Nan Liu Jian-Zhong Li Zhao-Nian Zou 《Journal of Computer Science & Technology》 SCIE EI CSCD 2016年第4期720-740,共21页
Low quality of data is a serious problem in the new era of big data, which can severely reduce the usability of data, mislead or bias the querying, analyzing and mining, and leads to huge loss. Incomplete data is comm... Low quality of data is a serious problem in the new era of big data, which can severely reduce the usability of data, mislead or bias the querying, analyzing and mining, and leads to huge loss. Incomplete data is common in low quality data, and it is necessary to determine the data completeness of a dataset to provide hints for follow-up operations on it.Little existing work focuses on the completeness of a dataset, and such work views all missing values as unknown values. In this paper, we study how to determine real data completeness of a relational dataset. By taking advantage of given functional dependencies, we aim to determine some missing attribute values by other tuples and capture the really missing attribute cells. We propose a data completeness model, formalize the problem of determining the real data completeness of a relational dataset, and give a lower bound of the time complexity of this problem. Two optimal algorithms to determine the data completeness of a dataset for different cases are proposed. We empirically show the effectiveness and the scalability of our algorithms on both real-world data and synthetic data. 展开更多
关键词 data quality data completeness functional dependency data completeness model optimal algorithm
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Model Study of Basin Soil Loss (BSL) in the Loess Plateau of China (Ⅰ)
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作者 王治华 黄联捷 《Science China Chemistry》 SCIE EI CAS 1993年第7期888-896,共9页
According to the influence of underlayer factor upon the basin erosion and in the support of Geographic Information System (GIS) of Loess Plateau(LPIS), the Gushanchuan Basin is divided into several regions with diffe... According to the influence of underlayer factor upon the basin erosion and in the support of Geographic Information System (GIS) of Loess Plateau(LPIS), the Gushanchuan Basin is divided into several regions with different erosion intensity. Correlating them to the BSL quantity, the complete soil loss model is established. By using this model, the soil loss quantity of the whole basin as well as each erosion intensity region can be estimated. 展开更多
关键词 UNDERLAYER complete soil loss model remote sensing data Geographic Informationh System——GIS relative erosion intensity.
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The driving effects of urbanization on economic growth and water use change in China: A provincial-level analysis in 1997-2011 被引量:23
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作者 BAO Chao 《Journal of Geographical Sciences》 SCIE CSCD 2015年第5期530-544,共15页
As one of the key issues in China's sustainable development, rapid urbanization and continuous economic growth are accompanied by a steady increase of water consump- tion and a severe urban water crisis. A better und... As one of the key issues in China's sustainable development, rapid urbanization and continuous economic growth are accompanied by a steady increase of water consump- tion and a severe urban water crisis. A better understanding of the relationship among ur- banization, economic growth and water use change is necessary for Chinese decision mak- ers at various levels to address the positive and negative effects of urbanization. Thus, we established a complete decomposition model to quantify the driving effects of urbanization on economic growth and water use change for China and its 31 provincial administrative regions during the period of 1997-2011. The results show that, (1) China's urbanization only contrib- uted about 30% of the economic growth. Therefore, such idea as urbanization is the major driving force of economic growth may be weakened. (2) China's urbanization increased 2352×10^8 m3 of water use by increasing the economic aggregate. However, it decreased 4530×10^8 m3 of water use by optimizing the industrial structure and improving the water use efficiency. Therefore, such idea as urbanization is the major driving force of water demand growth may be reacquainted. (3) Urbanization usually made greater contribution to economic and water use growth in the provincial administrative regions in east and central China, which had larger population and economic aggregate and stepped into the accelerating period of urbanization. However, it also made greater contribution to industrial structure optimization and water use efficiency improvement, and then largely decreased total water use. In total, urbanization had negative effects on water use growth in most provincial administrative re- gions in China, and the spatiotemporal differences among them were lessened on the whole. (4) Though urbanization helps to decrease water use for China and most provincial adminis- trative regions, it may cause water crisis in urban built-up areas or urban agglomerations. Therefore, China should construct the water transfer and compensation mechanisms be- tween urban and rural areas, or low and high density urban areas as soon as possible. 展开更多
关键词 URBANIZATION economic growth water demand complete decomposition model spatiotemporal dif-ference water resources compensation
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Photometric stereo for strong specular highlights 被引量:1
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作者 Maryam Khanian Ali Sharifi Boroujerdi Michael BreuB 《Computational Visual Media》 CSCD 2018年第1期83-102,共20页
Photometric stereo is a fundamental technique in computer vision known to produce 3D shape with high accuracy. It uses several input images of a static scene taken from one and the same camera position but under varyi... Photometric stereo is a fundamental technique in computer vision known to produce 3D shape with high accuracy. It uses several input images of a static scene taken from one and the same camera position but under varying illumination. The vast majority of studies in this 3D reconstruction method assume orthographic projection for the camera model.In addition, they mainly use the Lambertian reflectance model as the way that light scatters at surfaces.Thus, providing reliable photometric stereo results from real world objects still remains a challenging task. We address 3D reconstruction by use of a more realistic set of assumptions, combining for the first time the complete Blinn–Phong reflectance model and perspective projection. Furthermore, we compare two different methods of incorporating the perspective projection into our model. Experiments are performed on both synthetic and real world images; the latter do not benefit from laboratory conditions. The results show the high potential of our method even for complex real world applications such as medical endoscopy images which may include many specular highlights. 展开更多
关键词 photometric stereo(PS) complete Blinn–Phong model perspective projection diffuse reflection specular reflection
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Study on Characteristics of Steady Flow Condensation Heat Transfer in a Tube under Zero-Gravitation 被引量:2
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作者 Qn Wei(Harbin Institute of Technology, Harbin 150001 China)Hou Zengqi Zhang Jiaxun (Chinese Academy of Space Technology, Beijing 100086, China) 《Journal of Thermal Science》 SCIE EI CAS CSCD 1996年第3期217-222,共6页
In this paper, the annular flow. model for in tube completed condensation is employed to predict the steady flow condensation heat transfer characteristics in a tube under zero-gravitation. In this easel it is propose... In this paper, the annular flow. model for in tube completed condensation is employed to predict the steady flow condensation heat transfer characteristics in a tube under zero-gravitation. In this easel it is proposed that vapor condenses on the liquid film surface. Due to the effect of surface tension, the liquid exists in the form of liquid film ring contacting wall; when the velocity of vapor core decreases to zerol the condensation process ends. Putting forward the physical and mathematical models, the problem is solved and the multi-order equation of the thickness of liquid film is obtained, which includes terms of the pressure gradient along axial direction, the friction force between vapor and liquid on interface. By computational calculation, this model can be used not only to predict the thickness of liquid film, the condensation pressure gradient along the axial direction, but also to determine the Nusselt number, the condensation length and the total flow pressure drop of condensation etc. At the end, the calculation results of the necessary condensation length are compared approximately with those from the experiments, which are obtained on the test set-up placed horizontally in gravitation field, and the deviation is analyzed. 展开更多
关键词 zero-gravitation the annuler flow model for in-tube completed condensation thickness of liquid film condensation pressure gradient Nusselt number total flow pressure drop ofcondensation condensation length
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Influence of welding residual stresses on the ductile crack growth resistance of circumferentially cracked pipe
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作者 Xiaobo REN Odd M.AKSELSEN +1 位作者 Bård NYHUS Zhiliang ZHANG 《Frontiers of Structural and Civil Engineering》 SCIE EI 2012年第3期217-223,共7页
Welding residual stress is one of the main concems for fabrication and operation of steel structures due to its potential effect on structural integrity.This paper focuses on the effect of welding residual stress on t... Welding residual stress is one of the main concems for fabrication and operation of steel structures due to its potential effect on structural integrity.This paper focuses on the effect of welding residual stress on the ductile crack growth resistance of circumferentially cracked steel pipes.Two-dimensional axi-symmetry model has been used to simulate the pipe.Residual stresses were introduced into the model by using so-called eigenstrain method.The complete Gurson model has been employed to calculate the ductile crack growth resistance.Results show that residual stresses reduce the ductile crack growth resistance.However,the effect of residual stresses on ductile crack growth resistance decreases with the increase of crack growth.The effect of residual stress has also been investigated for cases with different initial void volume fraction,material hardening and crack sizes. 展开更多
关键词 residual stress ductile crack growth resistance complete Gurson model eigenstrain method
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Mass transfer mechanisms in fixed-bed adsorption of erythromycin 被引量:2
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作者 Ying SUN Jiawen ZHU +2 位作者 Kui CHEN Sheng ZHU Jie XU 《Frontiers of Chemical Science and Engineering》 SCIE EI CSCD 2008年第4期353-360,共8页
The equilibrium and kinetic characteristics of the adsorption of erythromycin to Sepabeads SP825 were determined.The equilibrium data in a batch system was well described by a Langmuir isotherm.The separation performa... The equilibrium and kinetic characteristics of the adsorption of erythromycin to Sepabeads SP825 were determined.The equilibrium data in a batch system was well described by a Langmuir isotherm.The separation performance was investigated in a fixed-bed system with respect to the adsorption superficial velocity,ionic strength and pH.A mathematical model was used to simulate the mass transfer mechanism,taking film mass transfer,pore diffusion and axial dispersion into account.The model predictions were consistent with the experi-mental data and were consequently used to determine the mass transfer coefficients. 展开更多
关键词 fixed-bed adsorption superficial velocity ionic strength erythromycin However investigations on the parameters governing the performance of this technology are still scarce.In the present work a polymeric and porous resin Sepabeads SP825 resin was used for its higher adsorption efficiency compared with the resins reported.The equilib-rium capacity of Sepabeads SP825 for EM in a batch system was established using a Langmuir isotherm.The effects of superficial velocity ionic strength and pH on the adsorption process were determined from the results of fixed bed experiments.And a model of the purification process was used to simulate the mass transfer mechanism which has taken film mass transfer pore diffusion and axial dispersion into account.The experimental adsorp-tion measurements were compared to the results calcu-lated from the model.The completion of these studies provide some essential parameters which are required in order to design a successful purification process and better understand the fundamentals of these process.
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