Determination penetration number

GrindabiUty is normally measured by determining the number of revolutions in a pulverizer that are required to achieve a given size reduction. This is an indirect measure of the amormt of work required for that size reduction. GrindabiUty increases slowly to a maximum at 90% carbon and decreases rapidly beyond this point. Hardness is ascertained by meastrring the size of the indentation left by a penetrator of specified shape pressed onto the coal with a specified force for a specified time. It changes only slightly between 70 and 90% carbon and increases rapidly beyond 90% carbon. 

Another tjrpical problem is to determine the number of neutrons or gamma rays that penetrate through a shield surrounding a reactor. As was pointed out by at least two speakers yesterday, the diffusion approximation, which can often give a lot of information about the interior of a reactor, is generally... 

There are several potential sources of radioactive materials that can contaminate water (see Chapter 4, Section 4.14). Radioactive contamination of water is normally detected by measurements of gross P activity and gross a activity, a procedure that is simpler than detecting individual isotopes. The measurement is made from a sample formed by evaporating water to a very thin layer on a small pan, which is then inserted inside an internal proportional counter. This setup is necessary because P particles can penetrate only very thin detector windows, and a particles have essentially no penetrating power. More detailed information can be obtained for radionuclides that anit y-rays by the use of gamma spectrum analysis. This technique employs solid-state detectors to resolve rather closely spaced y peaks characteristic of specific isotopes in the sample s spectra. In conjunction with multichannel spectrometric data analysis, it is possible to determine a number of radionuclides in the same sample without chemical separation. This method requires minimal sample preparation. 

In setting up their last mile home-delivery operations for fresh food, Peapod determines the number of time slots to offer in a day, the length of time slots, and time slots that would be active in a zip code of a city (Agatz et al. 2007). Peapod uses characteristics such as population density, web penetration, and historical demand data to define service requirements for each zip code. Because dehvery trucks may visit several zip codes in the duration of a single time slot (based mi... 

The radiation and temperature dependent mechanical properties of viscoelastic materials (modulus and loss) are of great interest throughout the plastics, polymer, and rubber from initial design to routine production. There are a number of laboratory research instruments are available to determine these properties. All these hardness tests conducted on polymeric materials involve the penetration of the sample under consideration by loaded spheres or other geometric shapes [1]. Most of these tests are to some extent arbitrary because the penetration of an indenter into viscoelastic material increases with time. For example, standard durometer test (the "Shore A") is widely used to measure the static "hardness" or resistance to indentation. However, it does not measure basic material properties, and its results depend on the specimen geometry (it is difficult to make available the identity of the initial position of the devices on cylinder or spherical surfaces while measuring) and test conditions, and some arbitrary time must be selected to compare different materials. 

The binding behaviour of benzene can be extrapolated to many other aromatic compounds such as naphthalene and benzene derivativesInterestingly, a large number of probe molecules contain aromatic rings and many of them will prefer the outer regions of micelles, whereas in bilayer systems, the same molecules prefer the interior of the aggregate ". Qearly these probes cannot be used to determine polarity of the micellar interior or the extent of water penetration therein . 

For HEPA filters, the major design paranieter is the system airflow, which can be used to establish the size and number of HEPA filters required. The penetration, resistance, and airflow are determined by the manufacturer before the filter is shipped from the factory." Table 13.7 gives the standard sizes for HEPA filters. 

When choosing diamonds for a particular drilling situation, there are basically three things to know. First, the quality of the diamond chosen should depend on the formations being drilled. Second, the size of the diamond and its shape will be determined by the formation and anticipated penetration rate. Third, the number of diamonds used also is determined by formation and the anticipated penetration rate. 

Corrosion rates in normal industrial atmospheres measured as loss of weight over a period are extremely uniform among the various alloys. Table 4.19, last column, gives the corrosion rates (in g m d" ) for a number of alloys determined at Clifton Junction in recent years. The highest value recorded (0-4 g m d ) is equivalent to a rate of penetration of 0-076 mm/y, which is appreciably less than that of mild steel. 

There are various methods for the determination of the surface area of solids based on the adsorption of a mono-, or polymolecular layer on the surface of the solid. These methods do not measure the particle diameter or projected area as such, but measure the available surface per gram or milliliter of powder. The surface measured is usually greater than that determined by permeability methods as the latter are effectively concerned with the fluid taking the path of least resistance thru the bed, whereas the adsorbate will penetrate thru the whole of the bed as well as pores in the powder particles. These methods appear to be more accurate than surface areas calculated from weight averages or number averages of particle size because cracks, pores, and capillaries of the particles are included and are independent of particle shape and size... 

A detailed account of transport phenomena in crystals is outside the scope of the present review, though it is relevant to point out that factors which determine the rate at which reactants penetrate a barrier layer include the numbers, distributions and mobilities of vacancies. Oleinikov et al. [1173] conclude that Arrhenius parameters are devoid of any physical significance if due allowance is not made for imperfection concentration, which may vary with temperature (and a [77]). 

Of crucial significance in deciding between various models have been estimates of the number of copper atoms required to transform the surface into a (2 x 3)N phase. This was the approach adopted by Takehiro et al 2 in their study of NO dissociation at Cu(110). They concluded that by determining the stoichiometry of the (2 x 3)N phase that there is good evidence for a pseudo-(100) model, where a Cu(ll0) row penetrates into the surface layer per three [ll0]Cu surface rows. It is the formation of the five-coordinated N atoms that drives the reconstruction. The authors are of the view that their observations are inconsistent with the added-row model. The structure of the (2 x 3)N phase produced by implantation of nitrogen atoms appears to be identical with that formed by the dissociative chemisorption of nitric oxide. 

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