Popping volume

Expansion volume is the most critical quality factor for popcorn (Hosney et al. 1983, Pordesimo et al. 1990,1991, Song et al. 1991). The popped volume is important because the commercial buyer purchases the popcorn by weight and sells it by volume. In addition, popcorn texture (tenderness and crispness) is positively correlated with popping volume. Most commercial popcorn has a 30- to 40-fold expansion. 

E. Lusas and L.W. Rooney (eds.). First edition. Technomic Pnblishing, Lancaster, PA. Metzger, D.D., Hsu, K.H., Ziegler, K.E., and Bern, C.J. 1989. Effect of moisture content on popcorn popping volume for oil and hot air popping. Cereal Chem. 66 247-248. Meuser, F., and Wiedmann, W. 1989. Extrusion plant design. Chapter 5 in Extrusion Cooking. C. Mercier, P. Linko and J.M. Harper (eds.). American Association of Cereal Chemists, St. Paul, MN. 

Song, A., and Eckhoff, S.R., Paulsen, M., and Litchfield, J.B. 1991. Effects of kernel size and genotype on popcorn popping volume and number of unpopped kernels. Cereal Chem. 71 464-467. 

A Commercial Popcorn Popping Popcorn Popper. We are constructing a 1-liter popcorn popper to be operated in steady flow. First tests in this unit show that 1 liter/min of raw corn feed stream produces 28 liter/min of mixed exit stream. Independent tests show that when raw corn pops its volume goes from 1 to 31. With this information determine what fraction of raw corn is popped in the unit. 

Different laboratories use different criteria for determining whether a drop-test resulted in an explosion ( go ) or failure ( no-go ). In many test facilities any visual observation of smoke, flash or flame, or any crackle, pop or bang detected by the operator is taken to signify a go result. Sometimes sound-meters are used to detect the audible signals of a drop test. In still more elaborate tests, the volume of gas, produced by a go result, is measured. In general, for sensitive explosives like PETN, distinguishing between go ... 

L. The problem tells you that the bag has an initial volume, V), of 1 L and an initial pressure, Pj, of 101.325 kPa (the pressure at STP). The temperature doesn t matter because it remains constant. The pressure inside the bag reaches 500 kPa before popping, so that value represents P. You can also leave... 

With portland cement concretes, deterioration takes the form of horizontal cracks, pop-outs, D-cracking, spalling and scaling. Salts used as deicing agents compound the problem. Early theories attributed the mechanism of failure to the 9 per cent volume increase when water converts to ice. "Critical saturation" -moisture filling more than 91 per cent of the voids was considered important. 

Fig. 1.31. Heavy-walled centrifuge-tube, rubber cap liner, and cap. ("Pop bottle reactor.) Tubes with volumes ranging from 20 to 250 mL are available from Lab Glass, North West Boulevard, Vineland, NJ 08360.

The presence of POPs in remote areas demonstrates the importance of long-range atmospheric transport in the environmental distribution of these compounds. The atmosphere, due to its large volume and elevated speed at which it can transport air masses over long distances, is the most important pathway for distribution of POPs into the environment [39, 40], POPs have vapour pressures (P, ) between 10-2 and... 

Despite many years of interest in the phase distribution of POPs, few predictive models are available. A Langmuir-type relationship, which Junge (1977) first proposed and Pankow (1987) later reviewed and critically evaluated, is the most popular model for estimating adsorption onto aerosols. The Junge-Pankow equation relates the fraction of particulate POPs (c >) to the saturation liquid-phase vapor pressure of the compound ( P Pa) and the surface area of particles per unit volume of air (8, cm2 aerosol / cm3 air). 

Several predictive approaches are available for estimating the fraction of POPs sorbed onto aerosols. The Junge-Pankow model assumes that gaseous POPs are adsorbed onto active sites on the aerosol. Key parameters in the model are particle surface area per unit volume of air (0), the liquid-phase vapor pressure of the compound ( P ) and a factor (c) which depends on the excess heat of desorption from the particle surface. 

In popping bubble wrap, the volume of the bubble is made smaller by pushing on it. This increases the internal pressure, causing the bubble to pop. 

A 14.5 cm3 sample of oxygen gas at 24.3°C is drawn into a syringe with a maximum volume of 60 cm3. What is the maximum change in temperature that the oxygen can be subjected to before the plunger pops out of the syringe ... 

In addition to the magnitude and number of potential sources, a number of factors can influence levels of indoor contamination. In the first instance, the relative ease with which different classes of POPs can undergo emission from products within which they are incorporated will influence indoor contamination. For example, while the production volume of TBBP-A far exceeds that of HBCD (BSEF, 2001), TBBP-A is present in far lower concentrations than HBCD in indoor air and dust (Abdallah et al., 2008). Abdallah et al. (2008) attributed this observation to the fact that the principal use of TBBP-A is as a reactive flame retardant, whereas HBCD is used as an additive flame retardant. While... 

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