Surface tension static

Figure 6.22 shows the effect of APG additives on the dynamic and the static surface tension for different mass concentrations, measured at 75 and 95 °C. The... 

As can be seen in Table 6.5, ONB in APG solution of concentration C = 100 ppm took place at significantly higher surface temperatures. It should be noted that the ONB in surfactant solutions may not be solely associated with static surface tension Sher and Hetsroni (2002). Other parameters such as heat flux, mass flux, kind of surfactant, surface materials, surface treatments, surface roughness, dynamic surface tension and contact angle need to be considered as well. 

Encouraged by the results from static surface tension measurements, we next ran force-area curves on 3N, 6N, and ION acids. As Figure 33 indicates, there is pronounced discrimination between the racemic and enantiomeric monolayers, and those differences are sharply dependent on the subphase acidity, as had been impUed by the surface tension behavior. 

Figure 33 is particularly instructive because it shows the drastically different responses to compression of the racemic monolayer and the enantiomeric ones. Consistent with static surface tension results (Fig. 32), the enantiomeric amide does not even spread as a mono-layer on 3Af H2SO4. On all three acid subphases, the racemic material... 

Equilibrium spreading pressures, like static surface tension measurements, provide a means to determine surface energies under equilibrium conditions. On lOA H2SO4, racemic crystals (Fig. 10) spread within 5 min to an equilibrium pressure of 8.6 dynes/cm, whereas about 8 hr was required by either (i )-(+)- or (5)-(-)- crystals to spread to a final pressure of 5.5 dynes/cm. 

A number of methods are available for the measurement of surface and interfacial tension of liquid systems. Surface tension of liquids is determined by static and dynamic surface tension methods. Static surface tension characterises the surface tension of the liquid in equilibrium and the commonly used measurement methods are Du Notiy ring, Wilhelmy plate, spinning drop and pendant drop. Dynamic surface tension determines the surface tension as a function of time and the bubble pressure method is the most common method used for its determination. 

Figure 7 also shows the effect of the surface tension of the spray liquid on ligament production. Whereas Curve A was obtained using sugar solutions of surface tension ca. 75-80 dynes/cm., Curve B was obtained by spraying water-in-oil emulsions whose static surface tension was 35 dynes/cm. 

It is also important to consider the dynamic surface tension in addition to the static surface tension since the firing frequencies experienced by the fluids are very rapid (up to 40 kHz on some print heads, or 40000 pulses per second ) and result in a dynamic environment. It has been theorized that an ideal ink would posses a high dynamic surface tension (to promote rapid meniscus recovery at high firing frequencies) and a low static surface tension (to achieve good substrate wet out). ... 

The dynamic surface tension curve can be divided into three parts the first equilibrium state represents values at low surface ages (Region 1 in Fig. 7), a rate limiting state (Region 2 in Fig. 7), and the second equilibrium state represented by the static surface tension (Region 3 in Fig. 7). 

Ideally, the equilibrium state 1 needs to be short, followed by a quick drop upon which the ink should reach the static surface tension so that the ink may wet out the substrate upon impact. Surfactants are commonly employed to lower the surface tension and increase the steepness of the decline in Region 2 on Fig. 7, so that the... 

This relationship holds for slow bubbling in the constant volume region, although the exponent may be nearer when static surface tension data are... 

SURFACE TENSION OF SURFACTANT SOLUTIONS 5.2.1 Static Surface Tension... 

The detachment of a ring or a plate (a Wilhelmy plate) from the surface of a liquid or solution is a static surface tension measurement method, which gives the detachment force of a film of the liquid and its extension from the liquid surface. These methods are less accurate than the capillary rise method, but they are normally employed in most surface laboratories because of their ease and rapidity. 

Static Interfacial Tension See Static Surface Tension. 

Static Surface Tension The static surface or interfacial tension is a synonym for the equilibrium surface or interfacial tension. 

Surface Work The work required to increase the area of the surface of tension. Under reversible, isothermal conditions, the surface work (per unit surface area) equals the equilibrium or static surface tension. 

Static Surface Tension A synonym for the equilibrium surface tension or interfacial tension. See Surface Tension. 

THE STATIC SURFACE TENSION OF EPOXY RESIN AND ITS ACETONE SOLUTIONS. 

THE STATIC SURFACE TENSION OF EPOXY RESIN AND ITS ACETONE SOLUTIONS. //ENGLISH TRANSLATION OF DOKLADY AKAD. NAUK SSSR 167 /6/ 1325-6,1966.//... 

Dynamic surface tension refers to the fact that the surface tension needs a certain time to reach a static value (time-independent or equilibrium value) due to diffusion of the surfactants to the interface and possibly rearrangements to find the thermodynamically favoured conformation. Note, however, that for pure liquids the dynamic and static surface tensions have the same values. 

Surface tension measurement techniques are divided into methods for solids and liquids. There are two modes for measuring the surface tension of liquids static and dynamic. Values reported in the literature are often static surface tensions of liquids. Tables 2.1-2.3 present a brief description of the common techniques for surface tension measurement of liquid and solid materials. Some of these methods have been described in further detail. 

Table 2.1 Static Surface Tension Measurement Methods for Liquids...

Measurements of static surface tension (SST) and DST using the Wilhelmy plate and overflowing circular weir methods have been described in detail in a previous publication [4]. The set of conditions specified for DST measurements yields a surface age of 0.1 + 0.05 s with low-viscosity solutions. 

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