Toaster

The uppermost hearth serves to dry the damp ore in the hot (ca 500°C) gases exiting the top of the toaster. These gases may contain up to 15% of the total cmde oxide and up to 6% sulfur dioxide, high enough to be fed to a sulfuric acid plant. In some pyrometaHurgical operations, desulfurization is continued in a sintering step. 

By the early 1980s high-gloss DMCs using low-profile resins were finding use in kitchen appliances such as steam iron bases, toaster end-plates and casings for electric fires. 

Kitchens window fasteners, toasters, can-openers, trim for cooker, washing machine and dishwasher, clips. 

Attention to iron metabolism is particularly important in women for the reason mentioned above. Additionally, in pregnancy, allowances must be made for the growing fetus. Older people with poor dietary habits ( tea and toasters ) may develop iron deficiency. Iron deficiency anemia due to inadequate intake, inadequate utilization, or excessive loss of iron is one of the most prevalent conditions seen in medical practice. 

Chromium makes up just 0.012% of the Earth s crust, yet it is an important industrial metal. The main use of chromium is in metal alloys. Stainless steel, for example, contains as much as 20% chromium. Nichrome, a 60 40 alloy of nickel and chromium, is used to make heat-radiating wires in electrical devices such as toasters and hair dryers. Another important application of chromium metal is as a protective and decorative coating for the surface of metal objects, as described in Chapter 19. 

Small household appliances Vacuum cleaners, toasters... 

One or two examples of the many possible are given for each (a) a battery and (b) a toaster or electric space heater. 

Sensors are used to add something extra to the functioning of an appliance. Some recent examples of this use of sensors are the Natura hairdryer, the Cucina toaster and the Senseo Crema coffeemaker. 

This process is also applied in the Cucina toaster. The toaster is fitted with an NTC sensor that monitors the temperature in the toasting chamber and adjusts the toasting time, if necessary. 

Of course, the first slice of bread needs longer to become golden brown and crispy than the ones that follow, because the toaster will have heated up properly by then. This also goes for the Senseo Crema, the latest sensation in coffee brewing. 

In Fig. 6.1, an attempt is made to show to what extent sensors have been penetrating the appliance market over the past years, a trend which is set to continue in the next decade. In the beginning, there were relatively simple sensors for temperature, pressure, flow, etc. Over the last years, non-contact measuring devices have attracted much attention, such as non-contact temperature monitoring for toasters or for hair blowers. The introduction of more complex sensor systems, such as water quality sensors or multi gas sensing artificial noses is imminent. 

A new application of thermopile sensors can be found in toasters, ensuring a more reliable control of the browning process, which makes toasting a healthier process. 

White goods, components for the wet side of domestic washing machines, dryers and dishwashers refrigerator parts, floor care and small appliances, house wares, kitchenware, good clarity parts, jug kettles toaster and iron parts... 

Some appliances, such as toasters, popcorn poppers, broilers, dishwashers, refrigerators, ovens, ranges, clothes dryers, and electric blankets are, or have been, manufacmred with asbestos-containing parts or components for thermal insulation. As a typical example, hair dryers with asbestos-containing heat shields were only recalled in 1979. Laboratory tests of most hair dryers showed that asbestos fibers were released during use. 

Describe the reaction engineering of a kitchen toaster. The reactions are thermal drying (which alone makes stale bread) and thermal decomposition and oxidation of starch, which requires temperatures of -300°C. [Recall that the bread appears white until it is nearly done, and then it browns quickly and blackens if left in too long. Recall also that good toast has a brown layer < 1 mm thick while the interior is still white and soft. The control of temperature profiles and heat transfer aspects are essential in producing good toast.]... 

Design a PFTR toaster. [This is a major type of reactor in the food industry.]... 

The Problem A local store is going out of business and has advertised that all items are 60 percent off the original price. You buy a toaster oven that s currently marked 49.95. What will you pay for the toaster oven after the store applies the discount ... 

You re pretty happy with your purchase of the toaster oven until, the next day, you see that the same store is offering to reduce the previously reduced price by another 20 percent. Does that mean that the new reduction is 80 percent, or is the reduction 20 percent of the previous 60 percent Is there even a difference Oh, yes, there is. 

I IThe filling of a hot apple pie can burn your tongue while the crust will not, even when the pie has just been taken out of the oven. A piece of toast may be comfortably eaten a few seconds after coming from a hot toaster, whereas you must wait several minutes before eating hot soup. 

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