Tension active

This issue focuses on the themes of certainty and doubt, fragility and tenacious identity, in the psychotherapeutic process. Newman s paper explores some central tensions in the relation between consciousness and unconsciousness. Rowan offers a masterly account of what he plausibly claims are established salient features of the psychotherapeutic process, in terms of the analogy of alchemy. Balick s account of the 7th UKCP Professional Conference evokes the tensions activated by the interface between neuro-science and psychotherapy. And Tan and Zhong face us with the challenge of a communally and certainty based method, in relation to some antisocial sexual patterns, which appears to be more effective than more cautious established Western approaches... 

Cassidy PS, Kerrick WG, Hoar PE, Malencik DA (1981) Exogenous calmodulin increases Ca " sensitivity of isometric tension activation and myosin phosphorylation in skinned smooth muscle. Pflugers Arch 392 115-120 Cavaille F, Janmot C, Ropert S, d Albis A (1986) Isoforms of myosin and actin in human, monkey and rat myometrium.Comparison of pregnant and non-preghant uterus proteins. Eur J Biochem 160 507-513... 

Elektorowicz M, Chifrina R, Konyukhov B. (1995). Behaviour of tension-active compounds used to clean up of contaminated manufactured gas plant sites. Land Contamination ... 

Monodesmosidic S. s. have a high surface tension activity, form strongly foaming, soap-like solutions in water, and on direct introduction into the blood circulation cause hemolysis of red blood particles even at high dilution they thus act as potent plasma and frsh toxins. Digitonin forms poorly soluble 1 1 complexes with cholesterol and other 3/3-hydroxy- sterols, this property is used for the isolation and analysis of digitonin. 

Surfactant The surfactant, also called tension-active agent, reduces the surface tension of continuous phase, avoids the coalescence and agglomeration of drops, and stabiUzes the emulsion. A suitable surfactant should be able to give microspheres a regular size and a small size distribution, guaranteeing a more predictable and stable drug release. The increase of surfactant concentration reduces the size of microspheres. The addition of surfactant lowers the surface tension of the continuous phase and the diminution of the latter one decreases the particle size. 

Now, the surface tension actively assists in reducing the film resistance to mass transfer, while viscous stresses thicken the films. Substituting Eq. (6.7) and using the definition of the capillary number, we obtain... 

Physical ageing can result from the spatial reorganization of polymer chains or segments (relaxation of enthalpy, volume, orientation or stress crystallization etc.), transport phenomena (penetration of a solvent, migration of additives) and superficial phenomena (e.g. cracking in a tension-active medium). 

It has been shown that the interfacialtension coefficient reduction upon addition of an interfacial tension active additive has identical mathematical form as the diameter of the disppersed phase- reduction of v,2 enables the shear stress to break drops into smaller ones more efficiently. This can also be concluded from the capillarity number ... 

The real functionality of film has been demonstrated by contraction tests in a tension-active medium at high temperatures [46, 47]. 

These surface active agents have weaker intermoiecular attractive forces than the solvent, and therefore tend to concentrate in the surface at the expense of the water molecules. The accumulation of adsorbed surface active agent is related to the change in surface tension according to the Gibbs adsorption equation... 

Adsorption may occur from the vapor phase rather than from the solution phase. Thus Fig. Ill-16 shows the surface tension lowering when water was exposed for various hydrocarbon vapors is the saturation pressure, that is, the vapor pressure of the pure liquid hydrocarbon. The activity of the hydrocarbon is given by its vapor pressure, and the Gibbs equation takes the form... 

The thickness of the equivalent layer of pure water t on the surface of a 3Af sodium chloride solution is about 1 A. Calculate the surface tension of this solution assuming that the surface tension of salt solutions varies linearly with concentration. Neglect activity coefficient effects. 

Derive the equation of state, that is, the relationship between t and a, of the adsorbed film for the case of a surface active electrolyte. Assume that the activity coefficient for the electrolyte is unity, that the solution is dilute enough so that surface tension is a linear function of the concentration of the electrolyte, and that the electrolyte itself (and not some hydrolyzed form) is the surface-adsorbed species. Do this for the case of a strong 1 1 electrolyte and a strong 1 3 electrolyte. 

Assume that an aqueous solute adsorbs at the mercury-water interface according to the Langmuir equation x/xm = bc/( + be), where Xm is the maximum possible amount and x/x = 0.5 at C = 0.3Af. Neglecting activity coefficient effects, estimate the value of the mercury-solution interfacial tension when C is Q.IM. The limiting molecular area of the solute is 20 A per molecule. The temperature is 25°C. 

In addition to lowering the interfacial tension between a soil and water, a surfactant can play an equally important role by partitioning into the oily phase carrying water with it [232]. This reverse solubilization process aids hydrody-namically controlled removal mechanisms. The partitioning of surface-active agents between oil and water has been the subject of fundamental studies by Grieser and co-workers [197, 233]. 

Heesemann J 1980 Studies on monolayers 1. Surface tension and absorption spectroscopic measurements of monolayers of surface-active azo and stilbene dyes J. Am. Chem. See. 102 2167-76... 

Where surface-active agents are present, the notion of surface tension and the description of the phenomena become more complex. As fluid flows past a circulating drop (bubble), fresh surface is created continuously at the nose of the drop. This fresh surface can have a different concentration of agent, hence a different surface tension, from the surface further downstream that was created earlier. Neither of these values need equal the surface tension developed in a static, equiUbrium situation. A proper description of the flow under these circumstances involves additional dimensionless groups related to the concentrations and diffusivities of the surface-active agents. 

Mechanisms of Leukocyte Adsorption. The exact mechanism of leukocyte adhesion to filter media is not yet fuUy understood. Multiple mechanisms simultaneously contribute to the adhesion of cells to biomaterials, however, physical and biological mechanisms have been distinguished. Physical mechanisms include barrier phenomenon, surface tension, and electrostatic charge biological mechanisms include cell activation and cell to cell binding. 

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