Mass per area

Using this equation, the approximate (T — T ) value required for a film of a thermoplastic copolymer to be dry-to-touch, ie, to have a viscosity of 10 mPa-s(=cP), can be estimated (3,4). The calculated (T — T ) for this viscosity is 54°C, which, for a film to be dry-to-touch at 25°C, corresponds to a T value of —29 "C. The calculated T necessary for block resistance at 1.4 kg/cm for two seconds and 25°C, ie, rj = 10 ° mPa(=cP), is 4°C. Because the universal constants in the WLF equation are only approximations, the T values are estimates of the T requited. However, if parameters such as the mass per area appHed for blocking were larger, the time longer, or the test temperature higher, the T of the coating would also have to be higher. 

In bulk water (free solution), the diffusive flux, given in units of mass per area per time, is related to the concentration by Pick s first law. 

M. .. area mass/density ratio (ratio of coating mass fo quartz mass per area unit)... 

Dry-cake mass per area is shown in Fig. 14.10 as a function of elapsed time during a given revolution of the drum. 

Each displacement component contributes two terms to Equation 3.58 one, proportional to p, arises from the kinetic energy associated with film translation another, proportional to arises from the potential energy associated with film strains (modes shown in Figure 3.29). The kinetic contribution causes a SAW velocity decrease in proportion to film mass per area (pfc) — the mass loading contribution. 

The rate of oxidation and/or oxide formation has been described with Hnear, parabolic, logarithmic, and inverse logarithmic rate laws [1,22,23]. The generally accepted rate of oxidation is given in units of mass per area, the mass of oxide product formed per area of metal, and is denoted as W. The fUm thickness x is proportional to the weight gain. 

For pure particle erosion, a value of n of the order of 3 is frequently found. This can be explained by a consideration of the kinetic energy of the particles hitting the surface. The total impact energy per area unit and time unit is Vi mv. m is the sum of the particle mass per area and time unit. At constant concentration c, m is... 

Shown in Fig. I is a typical adsorption isotherm for a single-component surfactant adsorbing from an aqueous solution surface for which the head group of the monomer has an attractive interaction, such as an anionic surfactant adsorbed on a positively charged surface. The x-axis is the equilibrium concentration of surfactant in solution, and the y-axis is the amount of adsorbed surfactant, in moles or molecules or mass per area or adsorbent weight. 

Amjy g is the deposited metal mass per area unit (cm ) and time (s) given by Faradays equation... 

Deposited metal mass per area and time unit (Eq. (12.5))... 

In impinged or laminated textures, attention must be paid to the uniformity of the texture. The distribution in the mass per area and in the form of the texture particle may not be so different along the geomembrane that... 

If diffuse reflection spectrometry is to be used for quality control purposes, it is essential to know the actual investigated sample volume, which is equivalent to the radiation penetration depth or the effective sample size meff- In a publication by Berntsson et al. [73], the effective sample size of pharmaceutical powders was investigated by the three-flux approximation presented above that they called the equation of radiative transfer (ERT) method, and an empirical method they called the variable layer thickness (VLT) method. In this publication, the effective sample size meg is defined as the mass per area of the sample at which its diffuse reflectance has reached 98% of the diffuse reflectance of a corresponding optically thick sample. 

A dust-lead hazard is surface dust that contains a mass-per-area concentration of lead equal to or exceeding 40 micrograms per square foot (pg/fC) on floors or 250pg/ft on interior windowsills based on wipe samples. A soil-lead hazard is bare soil that contains total lead equal to or exceeding 400 parts per million (ppm) in a play area or average of 1200 ppm of bare soil in the rest of the yard based on soil samples. 

In this book, we will frequently use the first definition in Table 8.2-2, implying that mass transfer coefficients have dimensions of length per time. If the flux is expressed in moles per area per time we will express the concentration in moles per volume. If the flux is expressed in mass per area per time, we will give the concentration in mass per volume. This choice is the simplest for correlations of mass transfer coefficients reviewed in this chapter and for predictions of these coefficients given in Chapter 9. Expressing the mass transfer coefficient in dimensions of velocity is also simplest in the cases of chemical reaction and simultaneous heat and mass transfer described in Chapters 16, 17, and 21. 

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