Anomalous shapes

PS/PHEM A particles in micron-size range were also obtained by applying the single-stage soapless emulsion copolymerization method [124]. But, this method provided copolymer particles with an anomalous shape with an uneven surface. PS or PHEMA particles prepared by emulsifier-free emulsion polymerization were also used as seed particles with the respective comonomer to achieve uniform PS/PHEMA or PHEMA/PS composite particles. PS/PHEMA and PHEMA/PS particles in the form of excellent spheres were successfully produced 1 iLitm in size in the same study. 

The chain-branching effect, A, is seen to counteract the termination effect, B, but does not overcome it. On the other hand, if B < A, chain-carrier production outruns elimination by termination, and the population begins to increase exponentially as the exponential in eqn 9.57 becomes dominant. When this starts to happen, the Bodenstein approximations for OH- and O and eqns 9.56 and 9.57 derived from them lose their validity. Moreover, with the accompanying rise in temperature and pressure, other steps enter the picture to produce a more complex behavior. A result is the anomalous shape of the detonation limit, shown in Figure 9.2. 

Three ESCA studies in the solid state have been published 92a,94,95). However, the unresolved S22) peak obtained in these studies had such an anomalous shape that an unequivocal assignment was not possible. As a result of this, different deconvolutions were reported. A fourth experiment carried out in the gas phase has been published 96). The spectrum consists of one sharp and one broad doublet (see Fig. 14 a). 

Surprisingly, the Zn diffusion profiles obtained by the radiotracer technique exhibited anomalous shapes with a second maximum near to the Cu(In,Ga)Se2 Se-... 

Lee SW, McDowell MT, Choi JW, Cui Y (2011) Anomalous shape changes of silicon nanopillars by electrochemical lithiation. Nano Lett 11 3034-3040... 

There have been several theories proposed to explain the anomalous 3/4 power-law dependence of the contact radius on particle radius in what should be simple JKR systems. Maugis [60], proposed that the problem with using the JKR model, per se, is that the JKR model assumes small deformations in order to approximate the shape of the contact as a parabola. In his model, Maugis re-solved the JKR problem using the exact shape of the contact. According to his calculations, o should vary as / , where 2/3 < y < 1, depending on the ratio a/R. 

Fig. 2.17. Fused quartz is known to have an anomalous softening with stress or pressure in both static and shock loading. The time-resolved wave profile measured with a VISAR system shows the typical low pressure ramp followed by a shock at higher pressure. The release to zero pressure is with a shock, in agreement with the shape of the pressure-volume curve (after Setchell [88S01]).

From this equation it can be seen that the depth of penetration depends on the angle of incidence of the infrared radiation, the refractive indices of the ATR element and the sample, and the wavelength of the radiation. As a consequence of lower penetration at higher wavenumber (shorter wavelength), bands are relatively weaker compared to a transmission spectrum, but surface specificity is higher. It has to be kept in mind that the refractive index of a medium may change in the vicinity of an absorption band. This is especially the case for strong bands for which this variation (anomalous dispersion) can distort the band shape and shift the peak maxima, but mathematical models can be applied that correct for this effect, and these are made available as software commands by some instrument manufacturers. 

An anomalous behaviour is found also for 4He, as can be observed from Fig. 2.9 the 4He specific heat shows a sharp maximum around 2.2K, corresponding to the transition to the superfluid state (He II). The characteristic shape of the C-T curve has baptized this transition with the name of A-transition . 

The structure of 11 2IBr is (TBP, TBP), which represents the first example of a T-shaped adduct of a selenium compound with IBr.39a The anomalous bond distances in ll-2IBr (Se-Br (A)/Se-I (A) 2.897(2)/2.606(2) and 2.766(2)/ 2.629(2) for the two Br-Se-I units, respectively) have been explained on the basis of different polarities of the two bonds and on the basis of the involvement of Br in intramolecular hydrogen bondings. Reactions and/or structures are similarly investigated for A-methylthiazolidine-2(3H)-selone (12), N-methylbenzothiazole-2(3H)-selone (13), tV,7V -dimethylbenzoimidazole-2(3H)-thione (14), and -selone (15) with bromine,39b,c and more recently, for 14 and 15 with IBr.39d In this last case, the prediction of a 10-1-2 adduct for 14 IBr and a 10-Se-3 adduct for 15 IBr from the DFT calculations has been experimentally confirmed.39d... 

The anomalous features are observed on well-ordered (111) surfaces in a variety of electrolytes over a wide range of pH (0-11), but the potentials at which the features appear and the detailed shapes of the I-V curves vary considerably. Specifically, the potential region (versus RHE) in which the features appear changes with anion concentration in sulphate and chloride electrolytes, but not in fluoride, perchlorate, bicarbonate or hydroxide electrolyte. In sulfate electrolyte, at constant anion concentration the region shifts (versus RHE) with varying pH, while in fluoride, perchlorate, bicarbonate and hydroxide electrolyte it does not. The use of UHV surface analytical techniques has established to a reasonable (but not definitive) extent that adventitious impurities are not involved in the anomalous process, i.e., the only species participating in the chemistry are protons/hydroxyIs, water and the anions of the solute. On the basis of the pH and anion concentration dependencies, I agree with the... 

A similar approach was taken by Moore [27], utilizing poly(phenyl acetylene) dendrimers with a dimethylbenzene moiety attached at the core of the dendrimer. An anomalous shift (41 nm) in the fluorescence spectra of the probe in various nonpolar hydrocarbon solvents was observed for G5 and G6, but not for G1 to G4. This observation confirmed significant in the size and shape changes for these dendrimers between G4 and G5. 

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