For capillarity

The driving force for capillarity is measured by the capillary pressure... 

In calibrating the scale it is essential to measure the total capacity of bulb A and capillary tube B, it is also necessary to measure accurately the cross-sectional area of B and C and to make them from the same tube or from tubes of exactly similar bore. The latter step eliminates the need for capillarity corrections. 

Animal manures are also usually most effective when incorporated into the soil if conservation of the nutrients is the primary aim. Discing into the soil immediately after application is usually the most effective practice. This provides for good contact and mixing at a depth sufficient for capillarity in the soil to maintain good moisture conditions and rapid nitrification. Under many conditions it is often easier to broadcast the manure on the unplowed field and turn it under. This is a fairly satisfactory procedure provided that the manure is exposed to the weather for only a short period, and provided... 

By unifying the excess concept and the theory of deformation and introducing the individual capillary quantities, the set of tools for capillarity is logically completed. All of the variables and relationships can be defined. 

Huber G, Mantz H, Spolenak R, Mecke K, Jacobs K, Gorb SN, Arzt E. (2005) Evidence for capillarity contributions to gecko adhesion from single spatula nanomechanical measurements. Proc Natl Acad Sci 102 16293—16296. 

Equation 11-3 is a special case of a more general relationship that is the basic equation of capillarity and was given in 1805 by Young [1] and by Laplace [2]. In general, it is necessary to invoke two radii of curvature to describe a curved surface these are equal for a sphere, but not necessarily otherwise. A small section of an arbitrarily curved surface is shown in Fig. II-3. The two radii of curvature, R and / 2[Pg.6]

Most of the situations encountered in capillarity involve figures of revolution, and for these it is possible to write down explicit expressions for and R2 by choosing plane 1 so that it passes through the axis of revolution. As shown in Fig. II-7n, R then swings in the plane of the paper, i.e., it is the curvature of the profile at the point in question. R is therefore given simply by the expression from analytical geometry for the curvature of a line... 

The film pressure is defined as the difference between the surface tension of the pure fluid and that of the film-covered surface. While any method of surface tension measurement can be used, most of the methods of capillarity are, for one reason or another, ill-suited for work with film-covered surfaces with the principal exceptions of the Wilhelmy slide method (Section II-6) and the pendant drop experiment (Section II-7). Both approaches work very well with fluid films and are capable of measuring low values of pressure with similar precision of 0.01 dyn/cm. In addition, the film balance, considerably updated since Langmuir s design (see Section III-7) is a popular approach to measurement of V. 

In the United States, a number of physical tests are performed on siUcon carbide using standard AGA-approved methods, including particle size (sieve) analysis, bulk density, capillarity (wettabiUty), friabiUty, and sedimentation. Specifications for particle size depend on the use for example, coated abrasive requirements (134) are different from the requirements for general industrial abrasives. In Europe and Japan, requirements are again set by ISO and JSA, respectively. Standards for industrial grain are approximately the same as in the United States, but sizing standards are different for both coated abrasives and powders. 

Reactive Hquid infiltration (45,68,90,93,94) is similar to the CVI process used to make RBSN. Driven by capillarity, a reactive Hquid infiltrates a porous preform and reacts on free surfaces. Reactive Hquid infiltration is used to make reaction bonded siHcon carbide (RBSC), which is used in advanced heat engines and as diffusion furnace components for semiconductor wafer processing. 

Several micromanometers, based on the liquid-column principle and possessing extreme precision and sensitivity, have been developed for measuring minute gas-pressure differences and for cahbrating low-range gauges. Some of these micromanometers are available commercially. These micromanometers are free from errors due to capillarity and, aside from checking the micrometer scale, require no cahbration. See Doolittle, op. cit., p. 21. 

Hollow carbon nanotubes (CNTs) can be used to generate nearly onedimensional nanostrutures by filling the inner cavity with selected materials. Capillarity forces can be used to introduce liquids into the nanometric systems. Here, we describe experimental studies of capillarity filling in CNTs using metal salts and oxides. The filling process involves, first a CNT-opening steps by oxidation secondly the tubes are immersed into different molten substance. The capillarity-introduced materials are subsequently transformed into metals or oxides by a thermal treatment. In particular, we have observed a size dependence of capillarity forces in CNTs. The described experiments show the present capacities and potentialities of filled CNTs for fabrication of novel nanostructured materials. 

Wetting and capillarity can be expressed in terms of dielectric polarisabilities when van der Waals forces dominate the interface interaction (no chemical bond or charge transfer) [37]. For an arbitrary material, polarisabilities can be derived from the dielectric constants (e) using the Clausius-Mossotti expression [38]. Within this approximation, the contact angle can be expressed as ... 

H. G. J. Mol, H.-G. Janssen and C. A. Cramers, Use of open-tubular trapping columns for on-line extr action-capillar y gas cliromatography of aqueous samples , 7. High Resolut. Chromatogr. 16 413-418 (1993). 

L. Mondello, M. Catalfamo, P. Dugo and G. Dugo, Multidimensional capillar-y GC-GC for the analysis of real complex samples. Part I. Development of a fully automated GC-GC system , 7. Chromatogr. Sci. 36 201-209 (1998). 

Figure 13.1 Monitor (FID) (a) and analytical (ECD) (b) channel responses for PCB congeners in Aroclor 1254, showing selection of the six heart-cut events Frr-st columns, HT8 second columns, BPX5. Reprinted from Journal of High Resolution Chromatography, 19, R. M. Kinghorn et al., Multidimensional capillar-y gas chr omatography of polychlorinated biphenyl marker compounds , pp. 622-626, 1996, with per-mission from Wiley-VCH.

The next two chapters are concerned with wetting and capillarity. Wetting phenomena are still poorly understood contact angles, for example, are simply an empirical parameter to quantify wettability. Chapter 6 reviews the use of scanning polarization force... 

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