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吸附柱出口温度随时间的变化规律及其数值模拟

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离子交换与吸附 2005年第1期21卷 17-26页

作者：李立清,唐新村,hans-jürgen rhm 湖南大学环境科学与工程系中南大学化学化工学院 Department of Mechanical Engineering University Bochum Bochum44780 Germany 长沙410082 长沙4100823

在不同温度 (15℃、20℃、25℃) 下,测试了活性炭 C40/4 吸附有机气体丙酮的吸附热引起吸附柱出口温度的变化。理论分析了吸附过程的能量守恒模型,在其他物质守恒,动量守恒和吸附平衡数学模型的基础上,采取有限差分方法,并借助计算软件 ... 详细信息

在不同温度 (15℃、20℃、25℃) 下,测试了活性炭 C40/4 吸附有机气体丙酮的吸附热引起吸附柱出口温度的变化。理论分析了吸附过程的能量守恒模型,在其他物质守恒,动量守恒和吸附平衡数学模型的基础上,采取有限差分方法,并借助计算软件 ATHENA VIUALWOrKBENCH 对模型进行了数值解。探讨了物质轴向扩散系数,吸附热对吸附柱出口温度随时间变化规律的影响,发现吸附质轴向扩散系数是一个很小的数,可忽略不计,从而简化了模型。数值计算结果与实验结果能很好地相吻合。为获得吸附过程中有效传热系数提供了有效的解决方法,并为吸附过程的设计、预测和优化提供支持。

关键词：活性炭丙酮吸附数值模拟吸附热

Anisotropic plastic deformation behavior of as-extruded ZK60 magnesium alloy at room temperature

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中国科学:技术科学 2010年第4期 453-453页

作者： hans j r Department of Materials Science and Engineering Norwegian University of Science and Technology

The anisotropic plastic deformation behavior of as-extruded ZK60 magnesium alloy at room temperature(rT)was investigated by compressive and tensile testing in different directions,*** loading axis oriented at 0°,45°and 90°to the extrusion *** relationship between texture and plastic deformation behavior were *** results show that the extruded ZK60 alloy exhibits a strong ring fiber *** mechanical properties are strongly orientation *** tension testing,the 0°specimen exhibited higher yield strength and lower *** compression testing,however,ZK60 alloy exhibited almost the same yield strength in three *** anisotropic plastic deformation behavior is due to strong fiber texture and the lower symmetry of the hexagonal close packed(hcp)structure of ZK60 alloy. The correlation between texture and mechanical behaviour offers the possibility to improve the mechanical properties of magnesium alloy by optimization of the material production process.

关键词： anisotropic plastic deformation behavior ZK60 Mg alloy texture mechanical property

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活性炭吸附丙酮及其脱附规律的实验研究

哈尔滨工业大学学报 2004年第12期36卷 1641-1645页

作者：李立清张宝杰曾光明 hans-jürgen rhm 湖南大学环境科学与工程系哈尔滨工业大学环境科学与工程学院 Dept.of Mechanical Engineering University BochumBochum44780

为认识吸附剂物质脱附规律,实验测试了在不同真空度、温度、吸附入口浓度和不同脱附初始浓度下活性炭C40/4对丙酮吸附及脱附的性能曲线,实验得出:吸附性能曲线斜率受进口浓度、操作压力的影响;脱附性能曲线斜率受脱附出口初始与脱附平... 详细信息

为认识吸附剂物质脱附规律,实验测试了在不同真空度、温度、吸附入口浓度和不同脱附初始浓度下活性炭C40/4对丙酮吸附及脱附的性能曲线,实验得出:吸附性能曲线斜率受进口浓度、操作压力的影响;脱附性能曲线斜率受脱附出口初始与脱附平衡浓度差、操作压力的影响;而温度、床层高度、吸附空塔速度只是让穿透曲线左右平移;脱附时真空度越大,脱附气体浓度越大,但脱附速度相应变小;在真空下脱附的脱附柱的出口浓度达到初始脱附浓度的一半时,脱附速度大大减缓,并且由于吸附剂微孔内的毛细管现象作用,在低于0.06～0.07Mpa时,脱附出口浓度开始出现较长时间的反弹和维持,然后才缓慢下降;各种因素所引起的操作温度变化不大,对吸附和脱附的速度影响不大.

关键词：吸附脱附真空脱附丙酮活性炭

CALCULATION OF THE YOUNG'S MODULUS OF AN ADSOrBED POLYMEr LAYEr

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Chinese journal of Polymer Science 2007年第1期25卷 95-105页

作者： rüdiger Stark Michael Kappl hans-jürgen Butt Max-Planck-Institute for Polymer research Ackermannweg 1055128 MainzGermany

Polymer layers adsorbed to a surface or in a confined environment often change their mechanical properties. There is even the possibility of solidification of the confined layer. To judge the stiffness of such a layer, we used the Hertz model to calculate the Young＇s modulus of the polymer layer in the confinement of AFM experiments with silicon nitride tip with a radius of curvature ofr ≈ 50 nm and a glass sphere attached to the cantilever r =5 μm. Since there is no visible indentation of the layer in the AFM experiments, the layer is either penetrated very easily, or the indentation is too small to be seen in a force curve. The latter would be the case for a polymer layer with a Young＇s modulus above 4 × 10^8 Pa in case of an experiment with a silicon nitride tip and 4×10^5 Pa in case of a glass sphere.

关键词： AFM PDMS PI Confined polymer Young's modulus Solidification.

High-resolution Induan-Olenekian boundary sequence in Chaohu, Anhui Province

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Science China Earth Sciences 2005年第3期48卷 291-297页

作者： hans j. hansen Geological Institute Copenhagen University Oster Voldgade 10 DK-1350 Copenhage Denmark

The West Pingdingshan Section in Chaohu, Southeast China’s Anhui Province is one of the potential GSSP candidates for the Induan-Olenekian boundary. Extensive study has been done on the Induan-Olenekian boundary strata at the section to meet the requirements of defining the GSSP precisely. This paper focuses on the boundary strata at the section to present a review of the main results achieved in recent years. The Induan-Olenekian boundary strata here cover an interval of about four meters at the West Pingdingshan Section, in which the key indices of defining the boundary and the chief transitional processes of some parameters at the boundary are included. The relationship between the boundaries defined by ammonoids and by conodonts is well clarified at the section. The magnetic polarity analysis shows that the boundary interval belongs to a normal polarity zone. Both the carbonate and organic carbon isotopes com- positions experienced a significant conversion in the boundary interval.

关键词： Lower Triassic, Induan-Olenekian boundary, GSSP, candidate, Chaohu of China.

recycling of automotive aluminum

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Transactions of Nonferrous Metals Society of China 2010年第11期20卷 2057-2063页

作者： jirang CUI hans j.rOVEN Department of Materials Science and Engineering Norwegian University of Science and Technology(NTNU)

With the global warming of concern,the secondary aluminum stream is becoming an even more important component of aluminum production and is attractive because of its economic and environmental *** this work,recycling of automotive aluminum is reviewed to highlight environmental benefits of aluminum recycling,use of aluminum alloys in automotive applications,automotive recycling process,and new technologies in aluminum scrap *** survey shows that newly developed techniques such as laser induced breakdown spectroscopy(LIBS) and solid state recycling provide promising alternatives in aluminum scrap *** with conventional remelting and subsequent refinement,solid state recycling utilizing compression and extrusion at room or moderate temperature can result in significant energy savings and higher metal yield.

关键词： recycling automotive aluminum sorting mechanical separation solid state recycling

Estimation of Pool Boiling Heat Transfer Coefficients of Ethanol-Water Mixtures

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Chinese journal of Chemical Engineering 1999年第2期7卷 95-103页

作者：谷俊杰 hans-jrgBart Lehrstuhl fur Thermische Verfahrenstechnik Universitat Kaiserslautern67653 KaiserslauternGermany

Based on the analysis of the principles of heat and mass transfer from the liquid bulk to bubble surface during nucleation, a new estimation method to predict the heat transfer of the nucleate pool boiling in binary mixtures is proposed in this paper by using the heat and mass transfer analogy (Colburn analogy) at the bubble surface transfer layers. With the use of Thome's concept of boiling range, an approximate method is derived to realize the calculation. The predicted results by this method are in good agreement with the experimental data from different sources.

关键词： heat transfer boiling water-ethanol mixture estimation

Micromechanical investigation of granular ratcheting using a discrete model of polygonal particles

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Particuology 2008年第6期6卷 390-403页

作者： Fernando Alonso-Marroquín hans B. Mhlhaus hans j. Herrmann Earth Systems Science Computational Centre & School of Physical Sciences The University of Queensland Earth Systems Science Computational Centre The University of Queensland Institut fr Baustoffe ETH-HenggerbergZrich

We use a two-dimensional model of polygonal particles to investigate granular ratcheting. ratcheting is a long-term response of granular materials under cyclic loading, where the same amount of permanent deformation is accumulated after each cycle. We report on ratcheting for low frequencies and extremely small loading amplitudes. The evolution of the sub-network of sliding contacts allows us to understand the micromechanics of ratcheting. We show that the contact network evolves almost periodically under cyclic loading as the sub-network of the sliding contacts reaches different stages of anisotropy in each cycle. Sliding contacts lead to a monotonic accumulation of permanent deformation per cycle in each particle. The distribution of these deformations appears to be correlated in form of vortices inside the granular assembly.

关键词： Granular systems Dynamics and kinematics of rigid bodies Molecular dynamics methods

From Single Droplet to Column Design

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Tsinghua Science and Technology 2006年第2期11卷 212-216页

作者： hans-jrg Bart Institute of Thermal Process Engineering TU Kaiserslautern D-67653 Kaiserslautern Germany

The technique state to design counter-current extraction columns is based on the performance of pilot plant experiments. The modelling is then either with the equilibrium or dispersion model, whereas in the latter the dispersion coefficient accounts for all hydrodynamic non-idealities. A new approach uses single droplet experiments to obtain the basic laws and functions governing droplet breakage, coalescence, relative velocity, and axial dispersion when using droplet populance balance models （DPBM）. The hydrodynamics simulation results show that the mean Sauter diameter, hold-up, and concentration profiles could be well predicted, which promotes the use of DPBM models for further applications in industrial scale.

关键词： single droplet column design countercurrent extraction droplet populance balance model