Lacy structure

To further complicate matters, when 30 ppm chloride ion is present and titanium cathode blanks are used for the copper deposition, an incomplete or lacy structure is obtained. If 30 ppm glue is, in turn, added to this solution, the effect of chloride ion is counteracted and complete coverage is again obtained. 

Figure 3. Type II "Lacy" Structure of Polypropylene Formed at High Cooling Rates (2000X)...

An important reason besides cleaning for using combinations of primary and secondary surfactants is to improve the quality and volume of foam. As discussed in Section II.A.2, some secondary surfactants such as betaines, amine oxides, and fatty alkanolamides also act as foam modifiers. They change the foams from a loose lacy structure generated by lauryl and laureth sulfates to rich and creamy foams. 

The amplitude of small fluctuations in the local concenuation increases in time as shown schematically in figure III - 26. In this way a lacy structure of a membrane is obtained, and the type of demixing observed is called spinodal demixing [23]. 

The polymer-surfactant complex has high surfeice viscosity and elasticity (i.e. surfeice viscoelasticity), both will enhance the foam stability (see below). The amphoteric surfactants such as betaines and the phospholipid surfeictants when used in conjunction with alkyl sulfeites or alkyl ether sulfeites can also enhance the foam stability. All these molecules strengthen the film of surfactant at the air/water interface, thus modifying the lather from a loose lacy structure to a rich, dense, small bubble size, luxurious foam. Several foam boosters have been suggested and these include fatty acid alkanolamide, amine oxides. Fatty alcohol and fatty acids can also act as foam boosters when used at levels of 0.25-0.5 %. Several approaches have been considered to explain foam stability (a) Surface viscosity and elasticity theory The adsorbed surfeictant film is assumed to control the mechanical-dynamical properties of the surface layers by virtue of its surface viscosity and elasticity. This may be true for thick films (> 100 nm) whereby intermolecular forces are less dominant. Some correlations... 

Melnyk R.A., Hewitt K.M., Lacy D.B., Lin H.C., Gessner C.R., Li S., Woods V.L. Jr, Collier R.J. Structural determinants for the binding of anthrax lethal factor to oligomeric protective antigen. J. Biol. Chem. 

The lac operon has three structural genes (genes that encode protein products), the lacX, lacY, and lacK genes. 

Lacy DB, Tepp W, Cohen AC, DasGupta BR, Stevens RC (1998) Crystal structure of botulinum neurotoxin type a and implications for toxicity. Nat Struct Biol 5 898-902... 

Three proteins, for which I did not have structural data, should also be mentioned, namely the so-called minibody [147-149] a Kunitz inhibitor domain of the human lipoprotein associated coagulation inhibitor (LACI-D1 Refs. 89 and 90) which resembles BPTI and CP-1, a designed scaffold zinc-finger [150], The minibody is a 61 aa designed... 

D. A., Lacy, M.J., Baldridge, J.R., Probst, P., Ulevitch, R.J., Persing, D.H., Hershberg, R.M. Structure-activity relationship of synthetic toll-like receptor 4 agonists. J Biol Chem 279 (2004) 4440-4449. 

A neutral ditopic receptor for AMP has been reported by Lacy et al. which was synthesized by coupling a UO2-salen to a thymine unit. This receptor binds H2PO4" and 9-butyladenine. The association constant in DMSO for adenosine 3 -phosphate was estimated to be 1200 M . The proposed structure for the complex is shown in Figure 67 [92],... 

Rind, D., R. Suozzo, N.K. Balachandran, A. Lacis, and G. Russell, The GISS global climate-middle atmosphere model, Part I Model structure and climatology. J Atmos Sci 45, 329, 1988. 

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