Surface Diffusion

Advances in instrumentation have made it possible in recent years to study the microstructure of inorganic materials at atomic resolution using the technique of high-resolution electron microscopy (HREM). Details of instrumentation have been described elsewhere [l], and applications and trends for HREM have recently been reviewed [2]. Although HREM is primarily a technique for studying bulk defects, it is increasingly also being applied in the profile-imaging mode to derive information about surfaces [3]. The high spatial resolution of the electron microscope makes it a valuable tool for the characterization of heterogeneous catalysts. This is evidenced by the growing number of studies wherein electron micrographs are being used to describe the morphology of a particular catalyst. Profile imaging is proving particularly useful in this regard for following changes in surface structure as a function of treatment conditions [4].     

表面粗糙度

从固体材料表面粗糙度在表面处理技术中的重要性出发,介绍了表面粗糙度的含义.应用最普遍的表面粗糙度的表示方法,即轮廓算术平均偏差Ra,以及另外两种表面粗糙度的表示方法:轮廓10点高度值Rz和轮廓最大高度值Rg.     

Variations of Surface Tension with Body and Surface Concentrations

Mathematical derivatives of surface tension with body concentration and with surface concentration are examined analytically for solutions in which the activity coefficient of the solute is taken as a linear function of solute concentration in the body, and as fixed at unity in the surface. As an approximation, the surface concentration is taken as a uniform value maintained throughout a surface domain extending from the geometrical surface to a fixed depth into the solution, at which the concentration changes as a step function to the body concentration. The writer accepts previous experimental and theoretical conclusions that for an ionic solute the increment of surface tension per surface ion increases with decreasing ionic radius. The Debye-Hückel equation for the activity coefficient of electrolytes predicts that the activity coefficient of an ionic solute increases with increasing ionic radius. Experimentally, this predicted dependence and its reverse are observed about equally often. For those solutes which behave according to the Debye-Hückel prediction it is found that a negative derivative must exist between the derivatives of surface tension with body and with surface concentration at sufficiently high values of the increment of surface tension per surface ion.     

Acoustic Surface Wave Measurements of Surface Cracks in Ceramics

Acoustic surface wave techniques were devised for detecting and characterizing surface cracks in ceramics. These techniques detect cracks at least as small as 60 μm deep on polished samples. The crack detectability was diminished by surface grinding, because of a background effect, attributed to backscattering from surface microcracks. Preliminary experiments conducted on turbine blades indicated that the techniques can be applied to components of complex shape.     

聚烯烃表面氧化处理的研究

研究了以高锰酸钾或重铬酸钾／水／浓硫酸＝５∶８∶１００（质量比）或２０％（质量分数）的过硫酸铵水溶液及氯化铁或硫酸铜作为催化剂对聚烯烃进行的表面氧化处理,并通过熔点和红外光谱及光电子能谱等方法对氧化反应和产品的结构进行了表征。研究表明,最佳氧化温度和时间分别为４５℃～６０℃与４５ｍｉｎ;用ＫＭｎＯ４／Ｈ２ＳＯ４／ＦｅＣｌ３／ＣｕＳＯ４,Ｋ２Ｃｒ２Ｏ７／Ｈ２ＳＯ４／ＦｅＣｌ３,Ｋ２Ｃｒ２Ｏ７／Ｈ２ＳＯ４／ＣｕＳＯ４体系对聚乙烯的氧化中,氧化深度依次减小,Ｃ原子的摩尔分数由未氧化时的８０．８０４％,分别降低为３１．９０７％、６９．９０５％和７８．６６９％;在ＦｅＣｌ３催化下,产品中Ｃｌ的含量普遍增加,而以ＫＭｎＯ４／Ｈ２ＳＯ４／ＦｅＣｌ３／ＣｕＳＯ４氧化时增加最多,但对Ｋ２Ｃｒ２Ｏ７／Ｈ２ＳＯ４／ＦｅＣｌ３氧化体系,Ｏ含量的增加相对较多     

材料表面改性技术

本文论述了材料表面改性技术各类型方法，包括工艺原理、特点及应用。     

Catalytic Aluminas: Surface Models and Characterization of Surface Sites

Abstract

In recent years polyurethanes have been confronted with several challenges. Some of these challenges have been overcome with the development of new catalysts. This review article covers recent developments in the field of polyurethane catalysis. An overview of the different types of catalysts, their applications, and their actuation mechanisms, followed by a general survey of the stability of one‐component polyurethane systems in which the latent catalyst is already incorporated is presented.     

电晕表面处理

本文叙述了广泛应用于粘接、印刷、染整、食品包装等方面的电晕表面处理装置的结构和原理,对影响产品质量的有关工艺、操作和设备的选型等方面也作了介绍.     

镁的表面处理

综述了镁及其合金的表面清洗，化学处理，阳极氧化，涂敷有机物等表面处理方法。     

Catalytic Aluminas: Surface Models and Characterization of Surface Sites

Aluminas have been used extensively as adsorbenu and active catalysrs and catalyst supponsm the pas. Already in 1197 the aluminadyzed dehydration of ettllnoi was dtscavered by Dutch chermsts: and S;rbatier [3] remewed the use of dumlnas as active cazaiysrs far vanous reacttons UI the second decade of thu century. She that time the applicazions of aluuuas m dycic pmcesses have mcreased tremendously. In tndustrral cualytic pmcesses, alumuus are mostiy used as catalyst suppons [4]. Oxides a d mued oxides ap well as tracuuion mauls and noble meare supported oa alumma. Thuscb. romaa-elumana catalysts are ktng used for the conversion of parafdns to olailnrc hydrocarbons, 10 hydrodealkplation of aromatics. and to a lesser exzm in catalyzic reforming. The larter process LS also caralyzed by molybdena-alumina, a cavlyst system whid is also active for malang toluene and ocher aromatics from satwed hydrocarc bons. It also dyzes the Isomerhation of pm. Great efions are presently be-made to nudy the surface chemlstry of these molybdena-alumma ysfs [5, 6]. The great mterest LD. ttuS catalyst and its detailed nature and properties are certadp reiated to the enormous imnortance of cobalt oxade-molybdenum omde-nlumlna as a widely u5ed Caulytic system for hydrodesuUunzaim, hydmdeoirrogemion, and hydmcracklng reacttans. Cenaialy one of the most imporrant appllcations of alumbas is its use as a support for nobie met tn cazalpzic reformtng, My, dunsinas may also be used as supports for the immobilt.? tioa of mommuclear complexes and of polynucieu me clusters, a fleld which hs recently begun to attraa the Wrest of cacaiytic chamlsts [7, 8].     

Hyperthermal Surface Ionization

Surface ionization of molecules with hyperthermal kinetic energy (1–20 eV) was found to be very efficient, demonstrating several unique features. We have used the technique of aerodynamic acceleration in supersonic seeded beams in order to obtain molecular kinetic energies in the range 1–20 eV. Three types of hyperthermal surface ionization (HSI) processes were observed: (a) surface-molecule electron transfer was demonstrated in the I₂/diamond system where negative molecular iodine (I⁻₂) ions were produced; (b) molecule-surface electron transfer was found for the anthracene molecule where positive molecular anthracene ions were generated; (c) hyperthermal surface-induced dissociative ionization (HSIDI) was observed in 1-iodopropane, 1-chloro-3-iodopropane, benzyl bromide, and many other molecules. In these processes, we have observed a large current of negative halogen ions and positive molecular residue ions (ion-pair formation). The mechanism of HSI is described in terms of electron transfer processes. It occurs due to a curve crossing between the neutral scattering interaction potential surface and the ionic interaction potential surface and nonunity reneutralization second curve crossing of the scattered molecules or fragment ions.     

表面形貌对初始滴状冷凝的影响

鉴于镁能与热水（冷凝液）反应,反应后镁表面的化学成分将发生变化,初始冷凝液核的形态将被保留在镁表面上,所以本实验采用金属镁作为冷凝表面。同时为了研究冷凝表面微观形貌同滴状冷凝之间的关系,在相近的冷凝条件下,选取不同磁控溅射条件下制备的镁膜作为冷凝表面,采用分形理论对镁表面冷凝前表面形貌的复杂程度进行量化研究,运用差分计盒维数法计算镁表面冷凝前表面形貌的分形维数。结果表明冷凝试件的表面形貌特征对初始滴状冷凝的液核数有较大影响,其分形维数不同,冷凝后镁表面初始液核数也不同。在实验的基础上,建立了能够反映表面分形维数对成核中心密度影响的定量关系式。     

Prevention of Low-Temperature Surface Transformation by Surface Recrystallization in Yttria-Doped Tetragonal Zirconia

The low-temperature (100° to 400°C) tetragonal to monoclinic transformation in yttria-doped tetragonal zirconia (Y-TZP) can be inhibited by a postsintering grinding and annealing treatment. The surface region so treated contains fine tetragonal grains which have recrystallized from the severely damaged ground surface. The various features of the recrystallized surface that may affect the lowtemperature transformation are analyzed.     

铝及铝合金表面处理后的表面特征和粘接特性

本文介绍了铝材表面处理的目的与要求、经过各种机械和（电）化学方法处理后的表面特性,如表面形貌、表面粗造度、表面化学组成、表面润湿特性、表面氧化物的环境稳定性及其粘度接特性。其中以磷酸阳极化作最后表面处理工序获得的效果最好,在此前的化学处理工序基本不影响最后表面处理效果。     

表面接触消毒技术

表面接触消毒具有高效，简便，无二次污染的优点，近年来在饮用水处理中得到广泛应用并迅速发展。本文重点介绍了表面接触消毒剂的研究现状，并对表面接触消毒技术的前景进行了探讨。