Temperature effect diagnostic with

Heat transfer in micro-channels occurs under superposition of hydrodynamic and thermal effects, determining the main characteristics of this process. Experimental study of the heat transfer in micro-channels is problematic because of their small size, which makes a direct diagnostics of temperature field in the fluid and the wall difficult. Certain information on mechanisms of this phenomenon can be obtained by analysis of the experimental data, in particular, by comparison of measurements with predictions that are based on several models of heat transfer in circular, rectangular and trapezoidal micro-channels. This approach makes it possible to estimate the applicability of the conventional theory, and the correctness of several hypotheses related to the mechanism of heat transfer. It is possible to reveal the effects of the Reynolds number, axial conduction, energy dissipation, heat losses to the environment, etc., on the heat transfer. 

It is difficult to correlate the kyi/k values with the operation of a hydride, proton or H atom transfer. The temperature dependence of the kinetic isotope effect, which is now easier to measure accurately, is more diagnostic of mechanism but has been applied mainly to organic systems. ... 

MCD spectroscopy in range 300 to 2000 nm at both ambient and liquid helium (4.2 K) temperatures can yield information about the spin, oxidation, and coordination states of each heme in a multiheme protein such as CCP (75). This technique, in combination with low-temperature X-band EPR spectroscopy, was used to great effect in characterizing the properties of the fully oxidized and MV forms of the P. aeruginosa CCP in solution. At 4.2 K, both hemes in the oxidized enzyme are low-spin ferric, with diagnostic features in the near infrared-MCD (NIR-MCD) spectrum consistent with one heme with His/Met axial coordination and the other with bis-histidine axial coordination this is entirely consistent with the crystal structure. In contrast, at room temperature only the low-potential (bis-histidine coordinated) heme in the C-terminal domain remains completely low-spin, whereas the high-potential (His/Met coordinated) heme exists as mixture of high- and low-spin forms 58). 

Table 4 summarizes a number of well-known theoretical diagnostic criteria for the estimation of intraparticle transport effects on the observable reaction rate. Tabic 5 gives a survey of the respective criteria for interphase transport effects. It is quite obvious that these are more difficult to use than the simple experimental criteria given in Tables 2 and 3. In general, the intrinsic rate expression has to be specified and, additionally, either the first derivative of the intrinsic rate with respect to concentration (and temperature) at surface... 

Attempts to increase the contact angles of the diagnostic liquids by changing metal immersion conditions were not effective with the ethyl alcohol-water solutions. These attempts included (a) increasing the concentration of D by a factor of as much as four, (b) prolonging the immersion period from 1 to 64 hours, or (c) raising the temperature of immersion from 20°C. to 50°C. 

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