Induction temperature response

Elevation of temperature increases tyrosinase activity, shortens the induction period and stimulates melanin formation within physiological limits. The enzyme activity is optimal in the pH range 6.1-1.2 during in vitro reactions 183). The temperature responses of melanin-stimulating hormones have also been studied (226). 

The tested induction heating solution employed a vacuum-formed insulating sleeve with helical grooves into which specialized low-resistance inductive cable was inserted. Again, the inductive coil was powered with a high-frequency inverter. Power output during the induction trials was adjusted to equal the heat deliveiy rate to the barrel previously provided by the band-heaters. This was done so that observed differences in temperature response time between band-heaters and induction would be due primarily to the way heat is delivered to the barrel (not how much is delivered, as that amount remained approximately constant). 

What could be the signal for the induction of the cold shock proteins It has been observed that shifting E. coli cells from 37 to 5 °C results in an accumulation of 70S monosomes with a concomitant decrease in the number of polysomes [129]. Further, it has been shown that a cold shock response is induced when ribosomal function is inhibited, e.g. by cold-sensitive ribosomal mutations [121] or by certain antibiotics such as chloramphenicol [94]. These data indicate that the physiological signal for the induction of the cold shock response is inhibition of translation caused by the abrupt shift to lower temperature. Then, the cold shock proteins RbfA, CsdA and IF2 associate with the 70S ribosomes to convert the cold-sensitive nontranslatable ribosomes into cold-resistant translatable ribosomes. This in turn results in an increase in cellular protein synthesis and growth of the cells. 

For any fixed batch crystallization temperature, the effective nucleation rate passes through a maximum even at high seed densities. It is suggested that the induction period r uired to activate the seed surfaces may be responsible for the lower initial nucleation rate observed when the supersaturation was higher. It is also suggested that agglomeration may have caused the observed phenomenon. 

In view of the above the following ignition tests ignition temperature tests are primarily of historical interest. They also serve to outline the difficulties encountered in trying to characterize quantitatively the response of explosives to heat. Quantitative treatment of explosion temperatures and delay to explosion (induction time) and the parameters of the explosive that affect these quantities will be presented in a future Vol under Thermal Explosions ... 

Figure 6.14 compares the results of line shape computations based on the isotropic interaction approximation with the measurement by Hunt [187], This spectrum does not have many striking features because of the relatively high temperature of 300 K. We notice only a broad, unresolved Q branch and a diffuse Si(l) line of H2 is seen other lines such as Si(J) with J = 0, 2, 3,. .. are barely discernible. Various dips of the absorption at 4126, 4154 and 4712 cm-1 are caused by intercollisional interference, a many-body effect which is not accounted for in a binary theory. Roughly 90% of the Q branch (in the broad vicinity of 4150 cm-1) arises from the isotropic overlap induced dipole component (XL = 01). The anisotropic overlap component (XL = 21) is a little less than one-half as intense as the quadrupole induced term (XL = 23). These two components with X = 2 are responsible for the Si line structures superimposed on the broad isotropic induction component which is of roughly comparable intensity near the Si line center. 

Dipole-moment measurements (in benzene) and low-temperature NMR studies (CDCI3-CFCI3 or CDC13-CC14 at -72 to -79°C) gave AG° values for other spiro systems. The AG° values shown in Table XIV are from the NMR measurements,199,200 Buttressing and inductive effects are probably responsible for variations in AG° values. The l-fert-butylpiperidine-4-spiro-2 -oxiran and -2 -thiiran adopt equilibria favoring the axial heteroatom con-formers (dipole-moment measurements) (Table XIV).201... 

In the phase separation process, however, it needed some induction period for the polymer to start the phase separation. Almost complete isomerization of the azobenzene pendant groups from the cis to the trans form is required to decrease the phase separation temperature below 19.5 °C. The phase separation process exhibited a non-linear response to the irradiation time or the number of photons. When the number of absorbed photons reached a critical value, the system underwent the phase separation and the polymer chain was shrunk. The photo-stimulated phase separation/dissolution cycle was not observed below 19.4 and above 26.0 °C. 

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