Cooling effects

It has a higher latent heat and a greater density producing an over all cooling effect which is about twice as efficient as ordinary ice. 

The metallic taste (12,19,20) is not ascribed to any special taste buds or mouth area. Along with pungency (the hot taste of peppers), astringency (the puckering taste of alum), and cold taste (the cool effect of menthol), the metallic taste is called a common chemical sense (21). 

Below about 0.5 K, the interactions between He and He in the superfluid Hquid phase becomes very small, and in many ways the He component behaves as a mechanical vacuum to the diffusional motion of He atoms. If He is added to the normal phase or removed from the superfluid phase, equiHbrium is restored by the transfer of He from a concentrated phase to a dilute phase. The effective He density is thereby decreased producing a heat-absorbing expansion analogous to the evaporation of He. The He density in the superfluid phase, and hence its mass-transfer rate, is much greater than that in He vapor at these low temperatures. Thus, the pseudoevaporative cooling effect can be sustained at practical rates down to very low temperatures in heHum-dilution refrigerators (72). 

Relative humidity at which water condenses on the apphed film as a result of evaporative cooling effects. 

Xyfitol is approved, according to 21 CFR 172.395, for special dietary uses at levels not greater than that required to produce its intended effect. Xyfitol is used in sugar-free chewing gum to provide sweetness, softness and a cooling effect. 

Menthol Manufacture. Of the menthol isomers, only (-)-menthol [2216-51 -5] and (+)-menthol [15356-70-4] are of commercial importance. The most important natural sources of (—)-menthol are the oUs of Mentha arvensis (75—90%) and Mentha piperita (50—65%). The main suppUers ate Japan, China, BrazU, and Taiwan for the former and the United States, CIS, Bulgaria, and Italy for the latter. (—)-Menthol is known for its refreshing, diffusive odor characteristic of peppermint. It also is known for its strong physiological cooling effect, which is useful in cigarettes, dentifrices, cosmetics, and pharmaceuticals. 

Hydrocarbons and carbon monoxide emissions can be minimised by lean air/fuel mixtures (Fig. 2), but lean air/fuel mixtures maximize NO emissions. Very lean mixtures (>20 air/fuel) result in reduced CO and NO, but in increased HC emissions owing to unstable combustion. The turning point is known as the lean limit. Improvements in lean-bum engines extend the lean limit. Rich mixtures, which contain excess fuel and insufficient air, produce high HC and CO concentrations in the exhaust. Very rich mixtures are typically used for small air-cooled engines, needed because of the cooling effect of the gasoline as it vaporizes in the cylinder, where CO exhaust concentrations are 4 to 5% or more. 

The heated-thermocouple anemometer measures gas velocity from the cooling effect of the gas stream flowing across the hot junctions of a thermopile supplied with constant electrical power input. Alternate junctions are maintained at ambient temperature, thus compensatiug for the effect of ambient temperature. For details see Bunker, Proc. Instrum. Soc. Am., 9, pap. 54-43-2 (1954). 

If the solute-rich gas entering the bottom of an absorption tower is cold, the liquid phase may be cooled somewhat by transfer of sensible heat to the gas. A much stronger cooling effect can occur when the solvent is volatile and the entering rich gas is not saturated with respeci to the solvent. It is possible to experience a condition in which... 

Installation of heat-exchange equipment to precool and dehumidify the feed gas to an absorber also deserves consideration in order to take advantage of the cooling effects created by vaporization of solvent in the lower sections of the tower. 

In fact, it would be even worse as a result of the equally reduced cooling effect of the fan at lower speeds. Since kW oc Nr T, kW would vary with speed, the torque remaining almost the same throughout the speed range. The motor would draw the same power from the supply as before, which, proportional... 

While breaking smaller currents, the formation of gas may not be adequate to provide the desired cooling effect. This is, however, immaterial because of less intensive arc formation requiring much less cooling. Extinction may be slightly prolonged but may be achieved by the next current zero. 

The hot-wire anemometer sensor is a very fine wire with a diameter of few micrometers and length of few millimeters. This wire is connected to a measurement bridge and an electrical current is fed through the wire. The wire is heated to a temperature above the air temperature and the air velocity is determined by the cooling effect of the wire. The voltage over the wire, U, is a function not only of the velocity but also of the excess temperature and the fluid properties in the following way ... 

Cooling effect Heat removed by a refrigerating appliance or heat exchanger. 

The [CBT]ig efficiency is replotted in Fig. 3.14, against (Tt,ITx) with pressure ratio as a parameter. There is an indication in Fig. 3.14 that there may be a limiting maximum temperature for the highest thermal efficiency, and this was observed earlier by Horlock et al. [8] and Guha [9]. It is argued by the latter and by Wilcock et al. [10] that this is a real gas effect not apparent in the a/s calculations such as those shown in Fig. 3.9. This point will be dealt with later in Chapter 4 while discussing the turbine cooling effects. 

In the cycle calculations de.scribed below [2], film cooling was as.sumed. Further, as described in Appendix A, various a.s.sumptions were made for the critical constants, as follows. The constant C in Eq. (5.13) was taken as 0.045, and within W, the cooling efficiency tJcooi as 0.7 and the film cooling effectiveness ep as 0.4. All were assumed to be constant over the range of cooling flows considered. 

In a particular blade row, for a given gas entry temperature Tgj, a cooling air entry temperature and an assumed allowable blade metal temperature Tbi, the blade cooling effectiveness eq is obtained. With ep = 0.4 and Pcooi = 0-7, then follows from Eq. (5.10). With C = 0.045 the cooling air flow fraction ip is obtained from Eq. (5.13). 

Tgi and T -, are usually determined from and/or specified for cycle calculation so that the cooling effectiveness o implicitly becomes a requirement (subject to 7hi which again can be assumed for a level of technology ). If and C are amalgamated into a single constant K, then... 

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