surfaceandinterface讲解
界面工程1
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2013/12/10
比表面（specific surface area）
比表面通常用来表示物质分散的程度，有两 种常用的表示方法：一种是单位质量的固体所具 有的表面积；另一种是单位体积固体所具有的表 面积。即：
Am
/m A = 或 AV A / V
式中，m和V分别为固体的质量和体积，A为其表 面积。目前常用的测定表面积的方法有BET法和 色谱法。
固-固界面
图1 Fe3Al-Al2O3梯度涂层的截面组织 200×
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材料成形加工之二——熔射及镀膜
等离子熔射法的镀膜
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IBDM法的镀膜
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材料界面现象之三——生物医学工程
Ti
钛合金与胫骨的界面
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立方体数 1 103 109 1015 1021
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比表面Av/（m2/m3） 6 ×102 6 ×103 6 ×105 6 ×107 6 ×109
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分散度与比表面
从表上可以看出，当将边长为10-2m的立方体分割 成10-9m的小立方体时，比表面增长了一千万倍。 可见达到nm级的超细微粒具有巨大的比表面积， 因而具有许多独特的表面效应，成为新材料和多相 催化方面的研究热点。 边长l/m 1×10-2 1×10-3 1×10-5 1×10-7 1×10-9
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8）Interfacial phenomena in metals and alloys 准备 9）学生讲解一 10）Fe-C共晶系凝固与界面能 11）Al-Si系合金凝固与界面能 12）Mg-Al合金成形与半固态凝固 13）其它
ProCAST操作手册翻译续1
目录THERMAL 热分析2 GEOMETRY ASSIGNMENTS 几何体分配3 MATERIALS ASSIGNMENT 材料分配4 INTERFACES ASSIGNMENT 界面设定9 BOUNDARY CONDITIONS ASSIGNMENT 边界条件设定15 PROCESS CONDITIONS ASSIGNMENT 运行条件设定20 INITIAL CONDITIONS ASSIGNMENT 初始条件设定21 RUN PARAMETERS ASSIGNMENT 运行参数设定24 FLUID FLOW & FILLING 流场和填充24 RADIATION 辐射28 STRESS 应力28 DATABASES 数据库29 MATERIAL DATABASE 材料数据库29 MATERIAL PROPERTIES 材料属性33 THERMODYNAMIC DATABASES 热力学数据库39下面是ProCAST2005软件自带操作手册前处理部分（PreCAST）的翻译内容，从75页开始，本人E文水平极为有限，中文水平也不甚高，翻译内容必有诸多错漏之处，希望各位不要见笑。
THERMALThermal modelThe Thermal module allows to perform a heat flow calculation, by solving theFourier heat conduction equation, including the latent heat release duringsolidification. The typical results which can be obtained are the following :• Temperature distribution• Fraction of solid evolution• Heat flux and thermal gradients• Solidification time• Hot spots• Porosity prediction热分析热分析模块热分析模块执行热流计算，通过傅立叶热传导方程，包含结晶过程的潜热计算。
path,surface,face三者的区别
"x3t8Z3W%RCAD/CAM之家论坛GFace用于剪切几个相交的surface或者face集合，自动计算它们之间的交线为剪切线，不需要通过SSI建立交线，也不需要建立实际的curve来作为剪切线。得到的结果是face。8C2b'd/f-B;\8T(a!f0p
,w$Q-v:N9F3L6D4wGTrim属于Patch creation->Face命令和Patch modification->Trim命令的组合。其主要功能就是批处理Face或者Trim。通过Faces All选项来控制得到的结果。（如果源曲面为Patch），若勾选此选项，则通过剪切得到Face，否则得到近似的Patch。'M$D;e9P'O5I/a'l2o
针对A面8p7T'a5N'g2I.U1h
第一步，SSI，第二步，FACE主大面，第三步，提取FACE面边界，保持低阶。第四步，光顺边界线，要求二视角曲率趁势OK。第五步，UNFACE已经FACE的面，记住不要选定CURVE。第六步，用光顺的边界线FACE大面，第七步，删除边界线，重新提取FACE面边界线。第八步，TRIM与之相交的面，执行MACTH。CAD/CAM之家论坛1W%a3S(H$K+0K&|5^7r7| O,F8y!q
)r%L$u4i3P;?4@4K*H在ICEM Surf中区别它们其实很简单，使用modify patch面板中的CtrlP命令，然后点击相应的面，出现控制点的就是patch，不出现控制点的就是face；有些时候也可以通过边界数量确定。
3f"I"f2a)I/|8{ -S"E"b:g4a%Z
8^5s;g5R!x !X4^9](|#w:v#O8{
surface and interface
– Later we’ll provide a fully microscopic (molecular) derivation as well.
Illustrative Examples
• Several examples are shown in the book.
• Figure II-4a illustrates a curved interface of zero mean curvature. (The principal curvatures are the inverses of the corresponding principal radii.)
• If we displace the surface along the normal, the change in surface area is
dA = (x1 + dx1)(x2 + dx2) - x1 x2 = x1dx2 + x2dx1
Thus, the change in surface free energy is dF = g(x1dx2 + x2dx1)
Capillarity
• Capillarity deals with interfaces that are sufficiently mobile to assume an equilibrium shape, e.g. thin films, liquids in air, liquids in liquids.
• Consider that figure. • We will use a different (but equivalent) notation.
• We denote the normal to the surface by n and the principal directions perpendicular to the normal by e1 and e2.
abaqus 中surface单元用法
一、概述abauqus是一款常用于工程仿真的有限元分析软件，在实际工程设计和分析中，经常会涉及到表面单元的应用。
本文将对abaqus中surface单元的用法进行详细介绍，并提供实例分析，旨在帮助工程师和研究人员更好地理解和应用abaqus中的surface单元。
二、surface单元简介1. surface单元的定义和特点在abaqus中，surface单元是用于描述或定义表面的有限元单元。
它通常用于绑定面、接触面、刚度面以及其他需要进行表面传力或表面接触分析的场景中。
表面单元的定义通常需要考虑到表面的几何特征和载荷条件，以便更准确地模拟实际工程中的表面行为。
2. surface单元的分类在abaqus中，常用的表面单元包括四边形表面单元、三角形表面单元以及高阶表面单元。
不同的表面单元适用于不同的具体场景和模拟要求，在实际应用中需要根据具体情况进行选择和使用。
三、surface单元在abaqus中的应用1. 表面单元的创建在abaqus中，可以通过预处理模块中的“Create Surface”命令来创建表面单元。
用户需要输入表面节点的坐标信息以及单元的几何属性、材料属性等参数，以确定表面的形状和性质。
2. 表面单元的加载在建立好表面单元后，可以通过加载模块中的“Surface Traction”命令来给表面单元施加外部载荷或边界条件。
这些载荷可以是压力、力、温度等，通过对表面单元的加载，可以模拟表面在不同工况下的行为。
3. 表面单元的接触表面单元在接触分析中发挥着重要作用，abaqus提供了丰富的接触模型和算法，用户可以通过设定接触类型、接触条件等参数来实现不同表面单元之间的接触行为。
四、实例分析以钢筋混凝土梁受弯为例，通过abaqus建立梁的有限元模型，并在梁的底部施加弯矩载荷，利用surface单元对梁底部的表面进行建模和加载。
通过仿真分析，在给定的载荷条件下，表面单元的应力分布和变形情况是否符合预期，评估表面单元在实际工程中的应用效果。
Surface and Interface Analysis Handbook
You have full text access to this contentSurface and Interface Analysis© John Wiley & Sons, Ltd.Impact Factor: 0.998ISI Journal Citation Reports © Ranking: 2009: 90/121 (Chemistry Physical)Online ISSN: 1096-9918Author GuidelinesFor additional tools visit Author Resources- an enhanced suite of online tools for Wiley InterScience journal authors, featuring Article Tracking, E-mail Publication Alerts and Customized Research T ools.∙Copyright Transfer Agreement∙Permission Request Form∙The National Institutes of Health Public Access InitiativeAuthor Guidelines∙General∙Manuscript Submission∙Copyright and Permissions∙English Editing∙Presentation of Papers∙Reference style and EndNote∙Citing EarlyView Articles∙Chemdraw rules∙Colour Policy∙Conventions used by SIA∙Article types published in SIA∙Further InformationGeneralSurface and Interface Analysis [SIA] is devoted to the publication of papers dealing with the development and application of techniques for the characterization of surfaces, interfaces and thin films. 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Interface使用的相关问题
Interface使⽤的相关问题Interface使⽤的相关问题（鄙⼈拙见，有错之处还请多多指出）西⽶2019.10.311.Interface的⽤途：对于体⽹格⽽⾔：Interface是⽤来解决某个⾯两边的体⽹格不共节点的问题，通过设置interface来实现节点数据的传输。
对于⾯⽹格⽽⾔：Interface是⽤来解决某个线两边的⾯⽹格不共节点的问题，通过设置interface来实现节点数据的传输。
2.在Fluent软件中出现Mesh Interfaces这个选项的⼏种情况：①线/⾯两侧⽹格节点没有对齐（分别针对2D/3D⽹格）②在两个体之间没有进⾏SCDM共享⾯设置（即两体之间存在相同的分别属于不同体的两个⾯），在耦合⾯位置存在两个⾯的信息③在两个⾯之间没有进⾏SCDM共享边设置（即两⾯之间存在相同的分别属于不同体的两个线），在耦合线位置存在两个线的信息在ICEM中如果没有重复⾯和重复边则不会出现②③两个情况。
3.实例：3.1 3D模型验证体⽹格不共节点的情况，出现Mesh Interface3.2 2D模型⾯⽹格不共节点的情况，出现Mesh Interface4.Mesh Interface的四个选项：①Coupled wall②Matching option③Mapped option④Static option耦合壁⾯选项（Coupled wall）通常情况下，在⽹格划分过程中命名的Interface在导⼊到Fluent中，软件默认Interface在流体和流体之间⽣成的是内部⾯（interior），即⽤interface连接计算域是相通的，流体可以穿过interface进⾏质量交换。
在⼀些情况下，我们希望流体之间只发⽣热量的传递（类似于管内外流体传热问题），则流体不能通过interface，此时我们可以将interface设置为Coupled wall，形成⼀个wall，只进⾏传热，不传质。
表面化学Surface and Interface Chemistry
Return
Textiles
Textile auxiliaries, Printing and dyeing agents, Finishing agents
Textile auxiliaries
Oil emulsions Anti-static agents Slipping agents Sizing agents Brightening agents …
Return
Printing and dyeing agents
Leveling agents Accelerating agents Retarding agents Dye-fixing agents
…
Finishing agents
Softeners Stiffening agents Anti-static agents Water-proofing agents
3. The solid-gas interface
• Adsorption processes of gases on solids • Surface reaction
4. The solid-liquid interface
• Contact angles and wetting • Ore flotation and detergency
between the Oxygen
inside the exhaust
manifold and air
outside the engine. If
this
comparison
shows little or no
Oxygen in, a
voltage is generated.
Fe(s) + 1/2O2(g) + H2O(l) Fe2+(aq) + 2OH-(aq)
SerDesinterface参考设计-CDR设计
SerDesinterface参考设计-CDR设计5 CDR设计CDR一直是比较热门的研究方向，现在比较主流的方法有接收端输入数据和本地时钟的关系将其进行分类。
常见的 CDR 拓扑结构可以分为如下的三大类：（1）采用反馈相位跟踪结构。
如PLL，DLL（Delay Locked Loop，延迟锁相环），PI（Phase Interpolator，相位插值器）和IL （Injection Locked，注入锁定）结构的 CDR。
（2）无反馈的基于过采样（Oversampling）结构的 CDR。
（3）采用相位同步但没有相位跟踪环路的CDR，如基于门控振荡器[（GatedOscillator）和高 Q 带通滤波结构的 CDR。
在FPGA内实现CDR属于纯数字逻辑实现方法，对于使用PLL或者DLL锁相的方式在PPGA芯片上是不能够被实现，FPGA内置的PLL 无法直接用于CDR，因此无反馈的基于过采样的结构是FPGA实现CDR的主流的方式。
早期FPGA实现时钟恢复电路的方法，基本都是首先利用FPGA 内部的锁相环产生N*f的高频时钟，然后再根据输入信号控制对高速时钟的分频，从而产生与输入信号同步的时钟信号，其中N决定了恢复时钟信号的相位精度，通常N等于8。
因此如果输入信号的频率为100MHz，则系统的工作频率就必须达到800MHz，对于中低端FPGA，如此高的工作频率显然无法承受。
虽然高端FPGA可以达到GHz的工作频率，但其高昂的价格不适合用于普通用户。
而其它基于中低端FPGA实现高速时钟恢复电路的方法，要么需要外部VCO模块，要么只能恢复数据而无法得到同步的时钟信号。
随后出现利用DLL与过采样想结合的方法，具体的实现过程为利用FPGA的PLL产生多个相位的时钟，每个时钟相位都有固定的相位偏差，如0度、45度、90度。
利用同一频率多相位的时钟对数据进行采样，其产生的效果与过采样时类似，但是也会带来一些问题，受到PLL的限制，输出的多相位频率个数不会太多，因此其对时钟的恢复误差会在360/M内，Ｍ为输出频率的个数，对于高速的通信，该方法是不适用，对于速率在200MHz以内的数据通信，该方法具有易实现，成本低，研发周期短的优势，非常适合在中低端的FPGA中，实现相对高速的通信。
flac3d interface参数
Flac3D Interface参数Flac3D是一款广泛应用于岩土工程领域的三维有限元分析软件。
在进行Flac3D分析时，需要设置一系列的参数来定义模型、材料属性、边界条件等。
其中，Interface参数是用于定义模型中不同部分之间的接触关系的参数。
本文将详细介绍Flac3D中的Interface 参数。
一、Interface参数简介在Flac3D中，Interface参数用于定义模型中不同部分之间的接触关系，包括接触面、接触属性以及接触算法等。
通过合理的设置Interface参数，可以模拟不同材料之间、不同结构之间的相互作用，为分析提供更为精确的结果。
二、Interface参数设置1. 接触面定义接触面是指模型中需要进行接触分析的两个面。
在Flac3D中，需要明确指定哪些面需要进行接触分析，以及这些面的接触属性。
通常，可以通过选择面、单元或节点等几何元素来定义接触面。
2. 接触属性设置接触属性是指接触面的物理性质，包括摩擦系数、弹性模量、泊松比等。
在Flac3D中，可以通过定义材料库来统一管理这些属性，以便于在不同的模型之间进行复用。
同时，也可以根据需要进行手动设置，以满足特定的分析需求。
3. 接触算法选择接触算法是指在进行接触分析时所采用的方法。
Flac3D提供了多种接触算法供用户选择，包括罚函数法、拉格朗日乘数法等。
选择合适的算法对于确保分析的准确性和稳定性至关重要。
根据模型的特点和需求，可以选择适合的算法以提高计算效率或提高结果的准确性。
4. 初始接触条件设置初始接触条件是指在分析开始时，各个接触面之间的初始状态。
这包括接触面的相对位置、法向方向、切向方向等。
合理的设置初始接触条件对于确保分析的正确性和稳定性至关重要。
在Flac3D中，可以通过设置初始条件模块来定义这些参数，以确保模型在分析开始时处于正确的状态。
5. 迭代方法选择迭代方法是Flac3D用于求解非线性问题的迭代算法。
在接触分析中，需要选择适合的迭代方法来确保收敛并获得准确的结果。
外墙界面剂使用说明
外墙界面剂使用说明英文回答：Exterior Wall Interface Agent Instructions for Use.I. Purpose.The exterior wall interface agent is a water-based, single-component primer designed to improve the adhesion between different substrate materials and subsequent coatings. It is suitable for use on a variety of surfaces, including concrete, masonry, metal, and wood.II. Surface Preparation.Before applying the exterior wall interface agent, itis important to prepare the surface properly. This includes:Cleaning the surface to remove any dirt, dust, or contaminants.Repairing any cracks or voids in the surface.Priming the surface with a compatible primer if necessary.III. Application.The exterior wall interface agent can be applied using a brush, roller, or spray gun. It is important to apply a thin, even coat to the entire surface area. Allow the interface agent to dry completely before applying any subsequent coatings.IV. Coverage.The coverage rate of the exterior wall interface agent will vary depending on the surface texture and porosity. As a general guide, 1 gallon will cover approximately 100-150 square feet.V. Drying Time.The exterior wall interface agent will typically dry to the touch within 1-2 hours. However, it is important to allow the interface agent to cure for at least 24 hours before applying any subsequent coatings.VI. Safety Precautions.The exterior wall interface agent is not considered to be a hazardous material. However, it is always advisable to wear gloves and eye protection when working with any chemicals. If the interface agent comes into contact with skin, wash it off immediately with soap and water. If the interface agent is ingested, seek medical attention immediately.VII. Storage and Disposal.The exterior wall interface agent should be stored in a cool, dry place. It is important to keep the container tightly sealed to prevent the interface agent from drying out. Dispose of any unused interface agent in accordancewith local regulations.VIII. Additional Information.The exterior wall interface agent is compatible with most types of paints and coatings. However, it is always advisable to test the interface agent on a small area before applying it to the entire surface.The exterior wall interface agent is not suitable for use on surfaces that are exposed to constant moisture or water.If the exterior wall interface agent is applied to a surface that is not properly prepared, it may not adhere properly and could lead to premature failure of the coating system.中文回答：外墙界面剂使用说明。
SurfInterfaceAna...
SURFACE AND INTERFACE ANALYSISSurf.Interface Anal.2001;32:210–213XRD and XPS studies on the ultra-uniform Raney-Ni catalyst prepared from the melt-quenching alloy†Hao Lei,1Zhen Song,1Xinhe Bao,1∗Xuhong Mu,2Baoning Zong2and Enze Min21State Key Laboratory of Catalysis,Dalian Institute of Chemical Physics,Chinese Academy of Sciences,Dalian116023,P.R.China2Research Institute of Petroleum Processing,Beijing100083,P.R.ChinaReceived23October2000;Revised19December2000;Accepted8January2001We present a novel method for preparing an ultra-uniform Raney-Ni catalyst,which includes melt-quenching,hydrogen treatment and leaching in an alkali solution.The resultant catalyst shows superior activity in the reaction of cyclohexanone hydrogenation.X-ray diffraction(XRD)and XPS have been employed to characterize the catalysts.As demonstrated,the pretreatment with hydrogen caused a distinct phase transfer of the Ni–Al alloys,forming more of the Ni2Al3component.In the subsequent leaching process,the Ni2Al3component shows high activity and the resultant catalyst exhibits high surface areas and small pores.Moreover,metallic Al in the hydrogen-pretreated alloy appeared to be leached more easily and thus the aluminium species remaining on the catalyst surface is aluminium oxide predominantly, which serves as a matrix to stabilize active Ni species on the surface.Copyright 2001John Wiley&Sons, Ltd.KEYWORDS:XRD;XPS;Raney-Ni;melt-quenching;hydrogen pretreatmentINTRODUCTIONRaney-Ni catalyst(skeletal catalyst)is used widely in many industrial processes involving hydrogenation.1To improve the catalytic performance,numerous approaches for obtaining highly active catalysts have been carried out in recent years.A novel procedure deriving from the manufacture of amorphous materials,including the preparation of Ni–Al alloys using melt-quenching and subsequent Al leaching in NaOH solution,has been found to be a promising method for obtaining ultra-uniform Raney-Ni catalysts2because of the advantages of the rapidly solidified materials,such as smaller grain size and lower degree of segregation.3In the process mentioned, pretreatment as a crucial stage to activate the melt-quenched materials usually gives rise to remarkable changes in the chemical composition and morphology,and the hydrogen treatment was recognized to play an important role in optimizing the character of the catalyst.4–6In the present investigation,an ultra-uniform Raney-Ni was prepared by extracting hydrogen-pretreated Ni–Al alloy obtained by melt-quenching.Both X-ray diffraction(XRD)and XPS have been employed to characterize the surface properties,e.g. the surface composition and the chemical states of the surface phase,as well as the structure of the resultant ŁCorrespondence to:X.Bao,State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics,Chinese Academy of Sciences,Dalian116023,P.R.China.E-mail:*************†Paper presented at APSIAC2000:Asia–Pacific Surface and Interface Analysis Conference,23–26October2000,Beijing,China. Contract/grant sponsor:Ministry of Science and Technology. Contract/grant sponsor:National Science Foundation of China.Raney-Ni catalysts and their variations induced by the active hydrogen treatment.The catalytic activity of the catalysts was measured in the cyclohexanone hydrogenation reaction. EXPERIMENTALParent alloy ribbons(¾50%Ni and50%Al,¾4.5mm wide and10–25µm thick)were prepared by melt-quenching with a cooling rate of106K s 1.After grounding to powder, the melt-quenched alloys were exposed to a high-purity hydrogen(>99.99%)flow at an ordinary pressure at¾500°C for pretreatment.The alloy powders then were cooled to room temperature and placed into20%(wt.%)aqueous sodium hydroxide at100°C for leaching.The as-prepared catalysts were rinsed with distilled water at100°C until neutralized.The samples werefinally washed with absolute ethanol three times,transferred to stoppered tubes and stored in absolute ethanol at room temperature.The catalyst was labeled R1.For comparison,another catalyst was prepared in the same but without hydrogen pretreatment,labeled R2.X-ray diffraction powder analysis was carried out on a Rigaku D/max- b instrument using nickel-filtered copper K˛radiation.The tube voltage was40kV and tube current was100mA.The samples were scanned at5°C min 1in 2Â.X-ray diffraction measurements were made within24h of catalyst preparation.The XPS data were acquired with Mg K˛radiation using afixed analyser pass energy of 108eV in a modified Germany Leybold LHS12MCD system equipped with facilities for UPS,XPS and ISS,and the binding energy values were obtained with reference to the C ls level (284.5eV).The samples were heated on a heatable sampleXRD and XPS of Raney-Ni catalyst 211Table 1.Structural characteristics of the Raney-Ni catalysts with and without H 2pretreatmentPhase composition of parent alloy (wt.%)S BET V pore Mean poreCatalysts Ni 2Al 3NiAl 3/m 2Ðg 1/ml Ðg 1diameter (˚A)Conversion (%)R187.412.61450.1129.498.0R281.718.21140.0931.485.0rod in a pretreatment chamber at a pressure of 10 9mbar and analysed in an analysis chamber below 10 10mbar.Surface area and nitrogen adsorption data at 77K were measured on American Micromeritics ASAP2000automatic surface area and pore radius distribution apparatus.The catalytic hydrogenation reaction of cyclohexanone was carried out at 90°C under a pressure of 4.0MPa for 30min,and the feedstock was a cyclohexanone–cyclohexane mixture containing 30%cyclohexanone.The reaction prod-ucts were detected by liquid chromatogram and the conver-sion of cyclohexanone to cyclohexanol was calculated.RESULTS AND DISCUSSIONTable 1shows the structural characteristics of the Raney-Ni catalysts with and without hydrogen pretreatment (R1and R2)and their catalytic performances in the hydrogenation reaction of cyclohexanone.Although the melt-quenched Ni–Al alloys have similar phase compositions to those of Ni–Al alloys obtained by conventional methods,7in which mainly the Ni 2Al 3and NiAl 3phases exist,the uniform microstructure,chemical composition and crystalline phase of the former differ from that of the latter,8resulting in the formation of ultra-uniform catalysts.In Table 1,it can be seen that the BET area and pore volume of R1are distinctly higher than those of R2,in contrast,the values of the mean pore diameter of R1are obviously lower.Moreover,the catalytic activity of R1appears to be much higher than that of R2.These apparent differences could be attributed reasonably to the difference in phase composition between the two alloys.C P S2θ/°Figure 1.The XRD patterns of parent alloys:(a)Ni–Al alloys obtained by melt-quenching;(b)hydrogen-pretreated Ni–Al alloys obtained by melt-quenching.As evidenced by the XRD results (see Fig.1)and based on the method of quantitative phase analysis,9it is concluded that the Ni 2Al 3phase increased in Ni–Al alloys after pretreatment,i.e.hydrogen pretreatment caused a phase transfer from NiAl 3to Ni 2Al 3in the alloy (Table 1).In the subsequent Al leaching of the alloy in NaOH solution,the Ni 2Al 3phase contributes mainly to the formation of the skeleton 10and easily forms Raney-Ni with a higher surface area because the residue formed from Ni 2Al 3was strong and remained attached to the substrate,whereas the leaching of NiAl 3led to the formation of nickel residue,which lacks strength and tends to disintegrate.11In consequence,the parent alloy containing more Ni 2Al 3phase will become more effective in forming the uniform Raney-Ni with smaller pores due to the rearrangement of Ni atoms.125060708090d cbaNi3p Al2pmetaloxidemetaloxideBinding Energy (eV)Figure 2.The Ni 3p/Al 2p XPS spectra of:(a)Ni–Al alloys obtained by melt-quenching;(b)sample (a)after leaching with NaOH;(c)sample (b)heated up to 200°C for 10min in a vacuum;(d)sample (b)heated up to 600°C for 10min in a vacuum.212H.Lei et al .In order to compare the surface compositions of R1and R2,XPS experiments were carried out,because XPS can give information on the chemical composition of the catalystin the first 20˚Afrom the sample surface.1Figures 2and 3present the XPS spectra of Al 2p/Ni 3p taken,respectively,from the parent Ni–Al alloys and the related catalysts heated at various temperatures in a vacuum;the corresponding XPS spectra of Ni 2p exhibiting the variations of chemical state of nickel on the surfaces are shown in Figs 4and 5.As indicated in Figs 2(a)and 3(a),the surfaces of the two parent Ni–Al alloys exhibit a pronounced Al enrichment,which is in accordance with theoretical predictions that on binary alloys the metal with the lower sublimation energy is concentrated at the surface.The surface was covered by small amounts of metallic aluminium (72.6eV)and much more aluminium oxide (74.4eV).Meanwhile,nickel is protected from oxidation by a passive aluminium oxide film.The result was consistent with the commercial Ni–Al alloys reported by Okamoto 13and Holm.14Furthermore,nickel [in Figs 4(a)and 5(a)]also exists in two states,i.e.metallic nickel (Ni 2p 3/2at 852.6eV)and nickel oxide (Ni 2p 3/2(in NiAl 2O 4)at 856.0eV).The approximately same surface composition between melt-quenched Ni–Al alloys (R1and R2parent alloys)and commercial Ni–Al alloys indicated that the melt-quenching method brought little alteration in surface composition.When the R1parent alloys were pretreated with hydrogen,5060708090abc doxideoxidemetal metalNi3pAl2pBinding Energy (eV)Figure 3.The Ni 3p/Al 2p XPS spectra of:(a)hydrogen-pretreated Ni–Al alloys obtained bymelt-quenching;(b)sample (a)after leaching with NaOH;(c)sample (b)heated up to 200°C for 10min in a vacuum;(d)sample (b)heated up to 600°C for 10min in a vacuum.840850860870880890db a ∗10c oxideoxidemetalmetalNi2p 3/2Ni2p 1/2Binding Energy (eV)Figure 4.The Ni 2p XPS spectra of:(a)Ni–Al alloys obtained by melt-quenching;(b)sample (a)after leaching with NaOH;(c)sample (b)heated up to 200°C for 10min in a vacuum;(d)sample (b)heated up to 600°C for 10min in a vacuum.the aluminium content stays almost unchanged,including metallic Al and Al oxide,but the nickel content,especially nickel oxide [in Figs 4(a)and 5(a)]obviously decreases,which indicates that nickel oxide is more easily reduced than Al oxide on the surface after hydrogen pretreatment.The surface properties of the two samples,as shown in Figs 2(b)and 3(b),however,appeared to be rather different after Al leaching in NaOH solution under the same conditions.The Ni/Al ratio on the surface of R2exhibits an essential reversion by comparing R2with the corresponding parent alloy,i.e.the content of nickel (metallic Ni and nickel oxide)is obviously higher than that of aluminium (metallic Al and aluminium oxide).In addition,there was more metallic Ni than nickel oxide [see Fig.4(b)]on the surface,but that of Al was less [see Fig.2(b)].Compared with hydrogen-pretreated alloys,however,the Ni/Al ratio of R1increased a little,which means that the surface of R1was basically covered by aluminium (mainly Al oxide),although the content of Ni,especially that of nickel oxide,increased after leaching [see Fig.3(b)and 5(b)].The lower metallic Al content shows that Al on the surface of the hydrogen-pretreated Ni–Al alloy is easily extracted,whereas Al oxides with high contents stabilize the system by avoiding sintering.15At the same time,the Ni on the surface of R1must be dispersed better than that of R2because of the smaller number of Ni atoms per unit area.Heat treatment at 200°C and 600°C,respectively,for 10min in a vacuum resulted in a different variation of Ni/Al ratio on the surface of the two catalysts.WhenXRD and XPS of Raney-Ni catalyst 213840850860870880890d b c a*10oxideoxidemetalmetalNi2p 1/2Ni2p 3/2Binding Energy (eV)Figure 5.The Ni 2p XPS spectra of:(a)hydrogen-pretreated Ni–Al alloys obtained by melt-quenching;(b)sample (a)after leaching with NaOH;(c)sample (b)heated up to 200°C for 10min in a vacuum;(d)sample (b)heated up to 600°C for 10min in a vacuum.R2was heated in a vacuum,the amount of aluminium oxides on the surface rose progressively with the increase in temperature,[Figs 2(c)and 2(d)].Synchronously,the nickel oxide on the surface appeared to be reduced into its metallic form.After heating at 600°C,the nickel oxide on the surface was reduced completely and the ratio of metallic nickel to aluminium oxides reached ¾1.5:1,which was calculated by peak areas with the method reported by Boudevilie 16after the spectra were fitted.The actual thermal reduction of the nickel oxides on the surface could be ascribed to an active disproportionating reaction between Ni oxide and Al,i.e.NiO C Al !Al 2O 3C Ni.The heat treatment,however,did not cause any obvious change in the Ni/Al ratio on the surface of R1and the aluminium stayed the dominant species on the surface,even when it was heatedto 600°C in a vacuum [Figs 3(c)and 3(d)].Furthermore,the surface was covered mainly by aluminium oxides and almost no metallic aluminium existed.It actually confirmed the use of aluminium oxide as a stabilizer,even at high temperatures.CONCLUSIONBy comparison of the XRD and XPS results of the two catalysts derived,respectively,from the parent Ni–Al alloys with and without hydrogen pretreatment,it becomes quite clear that the hydrogen treatment caused an actual phase transfer of the Ni–Al alloy,forming more Ni 2Al 3component in the alloy.The alkali extraction of aluminium from the Ni 2Al 3phase led to an effective formation of Raney-Ni with high surface area and small pores on which the enriched aluminium oxide served as a stabilizer to the active metallic nickel.In this case,the well-dispersed Ni on the aluminium oxide phase enhanced a high catalytic performance in the hydrogenation reaction of cyclohexanone.AcknowledgmentsThe authors gratefully acknowledge the financial support by the Ministry of Science and Technology and by the National Science Foundation of china.REFERENCES1.Fouilloux P.Appl Catal.1983;8:1.2.Deng JF,Li HX,Wang WJ.Catal.Today 1999;51:113.3.Li YZ.In The Technique and Materials of Rapid Solidification .Defense Industry Press:Beijing,1993;72.4.Katona T,Molnar A,Perczel IV,Kopasz C,Hegedus Z.Surf.Interface Anal.1992;19:519.5.Yanashita H,Yoshikawa M,Funabiki T,Yoshida N.J.Chem.Soc.Faraday Trans.I 1985;81:2485.6.Baiker A.Faraday Discuss.Chem.Soc.1989;87:239.7.Freel J,Pieters WJM,Anderson RB.J.Catal.1969;14:247.8.Wang Y,Shen JY.Chin.J.Catal.1998;19:163.9.Guo CL,Yao GD.Acta Phys.Sin.1985;34:1451.10.Robertson SD,Freel J,Anderson RB.J.Catal.1972;24:130.11.Bakker ML,Young DJ,Wainwright MS.J.Mater.Sci.1988;23:3921.12.Lu ZL,Wang R,Ke J,Chen H,Mu XH,Zong BN.Chin.J.Catal.1997;18:110.13.Okamoto Y,Nitta Y,Imanaka T,Teranishi S.J.Chem.Soc.FaradayTrans I 1980;76:998.14.Holm R,Storp S.J.Electron Spectrosc.Relat.Phenom.1976;8:139.15.Anderson JR.In Structure of Metallic Catalysts ,Academic Press:London,1975;230.16.Boudevilie Y,Figueras F,Forisser M,Portefaix JL,Vedrine JC.J.Catal.1979;58:52.。
第二章表面与界面现象
properties of solid surface
• surface roughness: uneven Surface roughness is defined as the ratio of real surface area to the plan area, and it is larger than 1 for all practical surfaces.
当我们用“表面”这个词的时候，是用来指某个“单相”的物理边界， 比如固体表面和液体表面等。
Interface and surface
In reality, we deal with an interface in all cases other than absolute vacuum conditions for solids, since every single phase is in contact with another phase such as solid–air,liquid–air contacts.
Adsorption and absorption
The term sorption encompasses both processes(adsorption and absorption), while desorption is the reverse of it. Adsorption is a surface phenomenon.
Wettability and repellency
Water droplet immersed in oil and resting on a brass surface
Same fluids as above, but resting on a glass surface
ICEMCFD中处理interface面
ICEMCFD中处理interface面Interface在CFD中应用得非常多，比如常见的应用MRF，SRF，MP以及滑移网格。
其实在有限元计算中也有类似的概念。
不过在固体计算中不叫interface，转而称之为耦合面或者干脆叫耦合。
interface 在CFD中多用于计算域间的数据传递，其通常成对出现。
interface 对上的网格节点不需要点对点对应，甚至可以是不同类型的网格，比如说一边是四面体而另一面是六边形。
1、关于Interface，有以下几点需要说明：（1）在网格划分软件中所设定的interface，导入到cfd中不一定能够识别，即使能够识别，也需要在求解器中设定interface的对应关系。
（2）interface是边界，所以不能出现在同一个域的内部。
一个区域的内部应该是wall或者interior。
2、ICEM CFD中进行Iterface面处理，有以下几种类型：（1）从同一个几何切割，但是仍然为一个域，切割的目的只是为了网格划分的方便（2）导入两个几何，建立它们的分界面（3）一个几何切割成多个几何，但是网格划分是独个进行的，建立它们的交界面。
（4）从同一个几何切割成多个域，设定切割面为interface3、第一种情况：一个几何体，一个区域对于这种情况，是不需要interface面的，切割的目的只是为了划分网格，比如划分混合网格，或者进行并行网格划分。
切割出的中间面，我们有两种处理方式：（1）我们可以将中间面上节点进行合并，然后在输出的时候设定中间面类型为interior（2）设定interface对。
这种方式是不用进行节点合并，直接导入到求解器中，求解器会自动进行识别，将中间面上网格识别为两个面（会自动创建shadow），我们只需要在求解器进行grid interface对的设定即可。
4、第二种情况：导入两个几何，设定分界面这种情况其实没什么好说的，分别设置分界面为单独的part，然后进行网格组装就可以了5、第三种情况：一个几何切割成多个几何，独立划分网格这其实和第二种情况是相同的，所不同的是几何切割放在ICEM中进行而已。
ansa学习笔记
1.面法向方向统一face——--orient；法向方向反向face—--—invert2.面投影，剪切3.合并边，面face—--topo4.面概念（surfs>Info）？？???5.概念面小删除,新建surface face delete surface-——coons6.概念面大利用已存在面建立一个新面faces--—new manual7.3d curve 交线curve—surf Int ;偏移curve-—-transf 投影cons---—project8.自由边间隙过大就将第2边粘贴到第一边（即将2去掉由1代替）cons-—-—paste，若出现白点，说明起点跟终点重合了，释放该点,HOT POINT—--release，将会重新出现很多自由边，用paste一一合并（注意去除hot point,HOT POINT—--DELETE）9.模型简化，删除小孔，CONS-—-FILL HOLE10.将边缘高度统一到10mm FACES—--——FLANGE【WIDTH】11.将圆角面变为尖角面FACES—--DACH12.当间隙过大时，使用FACES-——TOPO不能合并时，使用CONS—-—PATSE来合并,但注意一定要是正确匹配，即要一条边对应一条边,一一对应，若不对应,则要使用删除或增加，使用HOT POINT--Delete（删除），HOT POINTS—--PROJECT或INSERT（增加)13.边缘圆角变边缘尖角FACES--—-FLANG【CORNER】14.面划分FACES—---CUTS15.给面指定属性FACES--——SET PID16.几何检查：UNCHECKED 功能只显示执行SHADWO 功能失败的面.这样面一般都是细长的面和坏面。
17.给单元指定属性 MACRO—-——SET PID2d mesh1.从TOPO到MESH，Faces变Macro Area;CONS变Perimeter Segments;Hot Points变为白点，沿着Perimeter Segment布置着紫色的Perimeter Node2.Perimeter Node是由Cons Resolution决定的，要改变，就使用Marco—-—LENGTH3.决定网格类型,SHELL MESH---—Mixed4.划分网格SHELL MESH——--Free5.取消面的划分线，Marco-——-Join6.重新划分空白区域的网格SHELL MESH ——--——RE—MESH7.把两边缘线合并为一条分割线TOpo—-—DACH———DIVIDE FACE-selcet—joint8.将单元变增加一个节点，即将一个单元划分为两单元，密度加大，Perimeter—-—-number9.ANSA 自动把所有与所选边平行并处于各连续面上的边都增加一个节点。
FLAC3D 6.0 接触面
Interfaces创建原则
• 小表面与大表面接触时，接触面应建立在小表面上。 • 如果两相邻的网格有不同的密度，接触面应建立在密度大 的区域上（包含更多单元的区域）。 • 接触面单元的尺寸必须等于或小于相连的目标面的尺寸， 否则接触面单元必须重新细分成小单元。 • 接触面单元必须放置在会与其他网格面接触的目标面上 • 使用 Attach 命令连接的两个网格面不再建立接触面。
•
• 接触力仅在节点上传递。节点应力假定 在节点的代表区域上统一分布。每个节 点可以有自己不同的参数。
Interfaces理论
• FLAC3D中接触面是单面的。可以把接触面看作“收缩带”，在指定 面上拉伸，从而导致接触面和与之可能相连的其它任何面的相互刺入 变得敏感。 接触面单元可以通过接触面结点和实体单元表面（目标面）之间来建 立联系，接触面法向方向所受到的力由目标面方位所决定。 在每个时间步计算中，首先得到接触面节点和目标面之间的绝对法向 刺入量和相对剪切速度，再利用接触面本构模型来计算法向力和切向 力的大小。 Interfaces采用线性库伦剪切准则，来限制接触面节点上的剪切力。一 旦抗剪强度极限达到，法向和切向刚度、抗拉和抗剪强度、剪胀角的 设置可以增加目标面上的有效法向力。 若要考虑孔隙水压力的影响，需激活zone interface effective on来进行 有效应力计算。Zone interface permeability设置接触面是否为透水面。
Interfaces
ITASCA（武汉）咨询有限公司
Interfaces
• • • • • • • 概述 Interfaces基本理论 Interfaces本构模型 Interfaces创建原则 Interfaces建模命令 Interfaces参数选择 Interfaces角点问题
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固体表面实例
5. 固体表面力场
定义： 晶体中每个质点周围都存在着一个力场，在晶体 内部，质点力场是对称的。但在固体表面，质点 排列的周期重复性中断，使处于表面边界上的质 点力场对称性破坏，表现出剩余的键力， 称之 为固体表面力。 依性质不同，表面力可分为： 1）化学力 2）范德华力 (分子引力)
忽略了晶体内部周期性势场在晶体表面中断的影响，
忽略了表面原子的热运动、热扩散和热缺陷等，忽略了外 界对表面的物理化学作用等。 这种理想表面作为半无限的晶体，体内的原子的位置 及其结构的周期性，与原来无限的晶体完全一样。
2. 清洁表面
清洁表面是指不存在任何吸附、催化反应、杂 质扩散等物理化学效应的表面。这种清洁表面 的化学组成与体内相同，但周期结构可以不同 于体内。根据表面原子的排列，清洁表面又可 分为台阶表面、弛豫表面、重构表面等。
3、吸附表面
吸附表面有时也称界面。它是在清洁表面 上有来自体内扩散到表面的杂质和来自表面周 围空间吸附在表面上的质点所构成的表面。
根据原子在基底上的吸附位置，一般可分
为四种吸附情况，即顶吸附、桥吸附、填充吸
附和中心吸附等。
4、表面偏析
不论表面进行多么严格的清洁处理，总有 一些杂质由体内偏析到表面上来，从而使固 体表面组成与体内不同，称为表面偏析。
（1）化学力：本质上是静电力
当固体吸附剂利用表面质点的不饱和价键将吸附
物吸附到表面之后，吸附剂可能把它的电子完全给予 吸附物，使吸附物变成负离子（如吸附于大多数金属 表面上的氧气）；或吸附物把其电子完全给予吸附剂 ，而变成吸附在固体表面上的正离子（如吸附在钨上 的钠蒸气）。
（2）范德华(van der Walls)力（分子引力） 一般是指固体表面与被吸附质点（例如气体分子）之间相 互作用力。 主要来源于三方面： 1）定向作用力（静电力）：发生于极性分子之间 2）诱导作用力：发生于极性与非极性分子之间 3）分散作用力：发生于非极性分子之间
液—气界面
固—气界面
液—液界面
液—固界面
固—固界面
习惯上把液—气界面、 固—气界面称为液体表 面和固体表面。 通常，界面是一个薄 层；在极大数的情况下， 可以把界面视为一个二 维的平面而忽略它的厚 度。
一、固体的表面
1. 理想表面
1、 没有杂质的单晶，作为零级近似可将清洁表面理想为
一个理想表面。这是一种理论上的结构完整的二维点阵平 面。
-
Cl-Cl
TEMPORARY non-polar DIPOLE
INDUCED non-polar DIPOLE
Dispersion (weakest and very short-lived)
二、晶体表面结构
超细结构(微观质点排列)
1. 离子晶体表面
显微结构(表面几何状态)
表面力的作用： 液体: 总是力图形成球形表面来降低系统的表面能。 固体: 使固体表面处于较高的能量状态(因为固体不能流动), 只能借助于离子极化、变形、重排并引起晶格畸变 来降低 表面能，其结果使固体表面层与内部结构存在差异。
1.gas-liquid interface
2.gas-solid interface
3.liquid-liquid interface
4.Liquid-solid interface
5.solid-solid interface
表面:一个相和它本身蒸汽或真空接触的分界面。
界面:一相与另一相(结构不同)接触的分界面。
说明：
离子晶体MX在表面力
NaCl 晶 体
作用下，处于表面层的
负离子X在外侧不饱和， 负离子极化率大，通过
电子云拉向内侧正离子
一方的极化变形来降低 表面能。这一过程称为
离子晶体表面的电子云变形和离子重排
松弛，它是瞬间完成的， 接着发生离子重排。
NaCl 晶 体
从晶格点阵稳定性考虑
作用力较大，极化率小
H
H C H
H
C H H H
H
C H
H
C H H
NOT Dipole-Dipole
2) 诱导作用力
d+ H
Cl
d-
e- e- e- e- e- e- e- ee d+ ee - ee- e- e e ee-
Ar
d-
A DIPOLE (it’s polar)
INDUCED non-polar DIPOLE
Dipole – Induced Dipole (weak and short-lived)
3) 分散作用力
e d+ - e-e ee ee - e- - de e- e- e-
e-
Cl-Cl
e-
e-
e
- e-
e- e e- e- e- e- e- ee e dee- ed+ e- e- e e e-
的正离子应处于稳定的 晶格位置而易极化的负
离子受诱导极化偶极子
排斥而推向外侧，从而 形成表面双电层。重排
结果使晶体表面能量趋
离子晶体表面的电子云变形和离子重排
实际固体表面的不均匀性
表现在： (1) 绝大多数晶体是各向异性，因而同一晶体可以有许多性 能不同的表面。
(2)同一种物质制备和加工条件不同也会有不同的表面性质。
(3)晶格缺陷、空位或位错而造成表面不均匀。 (4)在空气中暴露，表面被外来物质所污染，吸附外来原子 可占据不同的表面位置，形成有序或无序排列，也引起表 面不均匀。 (5) 固体表面无论怎么光滑，从原子尺寸衡量，实际上也是 凹凸不平的。
（1）台阶表面 台阶表面不是一个平面，它是由有规则的或不 规则的台阶的表面所组成
[110] [112]
[111]
周期
有序原子台阶表面示意图
（2） 弛豫表面 由于固相的三维周期性在固体表面处突然中断， 表面上原子产生的相对于正常位置的上、下位移 ，称为表面弛豫。
（3）重构表面
重构是指表面原子层在水平方向上的周期性不 同于体内，但垂直方向的层间距则与体内相同。
相对而言，范德华力比离子 键力或共价键力弱得多
1) 定向作用力（静电力）
d+ 与 d – 互相有吸引作用 静电吸引 e+ e+
氟代甲烷(CH3F) – 沸点= 194.7 K polar or non-polar?H H Nhomakorabea H H
d+
d-
F
d+
Dipole-Dipole
H
C H
F
d-
乙烷(C2H6) – 沸点= 184.5 K polar or non-polar?