Crowd behavior

Strecker, E. A. Beyond the Clinical Frontiers A Psychiatrist Views Crowd Behavior. New York Norton, 1940. 

Observed deviations from ideality are attributable to thiazole selfassociation. Such self-association is influenced by steric crowding as indicated by the behavior of methylthiazoles. The constants of selfassociation have been estimated for benzene solutions of thiazole (Kassoc = 3.2 at 5.5°C) and 5-methylthiazole at 6.5°C). 

Additional officers arrived as the crowd grew, and Burns continued his bizarre behavior. A decision was made to remove Burns and... 

One characteristic of shear banded flow is the presence of fluctuations in the flow field. Such fluctuations also occur in some glassy colloidal materials at colloid volume fractions close to the glass transition. One such system is the soft gel formed by crowded monodisperse multiarm (122) star 1,4-polybutadienes in decane. Using NMR velocimetry Holmes et al. [23] found evidence for fluctuations in the flow behavior across the gap of a wide gap concentric cylindrical Couette device, in association with a degree of apparent slip at the inner wall. The timescale of these fluctuations appeared to be rapid (with respect to the measurement time per shear rate in the flow curve), in the order of tens to hundreds of milliseconds. As a result, the velocity distributions, measured at different points across the cell, exhibited bimodal behavior, as apparent in Figure 2.8.13. These workers interpreted their data... 

Although it may be intended that current should be shared between 106 emitters, in practice there is huge current crowding so that emission occurs from only a few of them, perhaps 1 or 10 in 105. This has two severe consequences. First, the emission site density is much lower than might be expected from the nanotube density. Second, the operating emitters can easily exceed their maximum currents and burn out, passing the emission onto those with the next highest p value, and so on. This leads to unstable emission behavior [27]. 

One would conclude that / must approximately equal 28 for this process Hofrichter et al found a similar behavior in nucleation of human hemoglobin S (HbS) the apparent reaction order for the nucleation of HbS aggregation was about 32 (See Hemoglogin S Polymerization). Of course, such analyses are not fully justifiable, because one cannot assume ideality in the solution properties at high protein concentrations (See Molecular Crowding). 

Ship-in-Bottle Synthesis of Sterically Crowded Fe-Phthalocyanines in NaY Zeolite Hosts and Their Catalytic Behavior in Regioselective Oxidation of Alkanes... 

A further point of interest is that in both the dimeric and trimeric species shown, the beryllium atom still has a vacant orbital available which may be used in adduct formation without disruption of the electron-deficient bond. This type of behavior leads to the formation of dimers with four-coordinate beryllium atoms, e.g., structure XX (86). This structure has been determined in the solid state and shows that the phenylethynyl-bridging group is tipped to the side, but to a much smaller extent than observed in the aluminum derivative (112). One cannot be certain whether the distortion in this case is associated with a it - metal interaction or is simply a result of steric crowding, crystal packing, or the formation of the coordination complexes. Certainly some differences must have occurred since both the Be—Be distance and Be—C—Be angle are substantially increased in this compound relative to those observed in the polymer chain. 

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